Yeah, that was something I always forgot when I was studying german.

Yeah, romanian has it as well, we use them like in english.

I'm only fluent in 3 languages and English is the only one.

I don't know how capitals are related to multilingualism but anyway, I speak Albanian as a mother tongue, English fluently and German at a considerably good level and also speak Italian at almost level B1, and out of these three, German has a quite strange capitalisation rule, since all the nouns, regardless of their type (proper, concrete, abstract) have to be capitalised. It took me long to acquire this rule. So John, Wind, Car, AMerica, Cat, are all written in capitals.

Yes, German has weird capitalization rules. Spanish is very similar to English. But we have signs for opening questionmark and exclamation point, like: ¡Hello! ¿How are you today?

I don't remember the history of capital letters right off, but they're related to manuscripts, in other words books where everything was written or copied by hand. But also in manuscripts, words were often written without spaces. Fun fact, the "X" in Xmas is actually a Christian abbreviation from manuscripts, where X represented the Greek letter chi, which also looks like an X, the first letter of Christ in Greek. It was used to save space, because paper and other writing materials were valuable, not to mention saving some labor. If I recall rightly, capital letters were often decorated as well, and made fairly large.

Wall of text coming up.
I searched about nouns in German, and here is what I got.
As @Connor and others said, the German language, unlike English, uses cases. Cases show what tense a particular noun is in (Case = Subject, Direct Object, Indirect Object, Possessive). German capitalizes the nouns for the reader, so that we can easily identify them while we're reading. Instantly when we look at a German text, we know what word is a noun. Once we know what word is a noun, we can look at the definite (der, die, das) or indefinite (ein, eine) articles to see what case the noun is in (Nominative/Subject, Accusative/Direct Object, Dative/Indirect Object.

Coming to capital letters in English.
Capital letters in Modern English derive from an Old Roman script used in the a.d. 200s. In those days, all caps was all there was! Lowercase letters hadn’t been invented yet, so capital letters were used for everything.
People have been using all caps for thousands of years—not to shout at everyone, but to convey “grandeur,” “pomposity,” or “aesthetic seriousness.” These uppercase letters were called majuscule, which evokes their majestic functions.
Because everything was hand-written in those days, there was soon a need to write books and documents more quickly. Scribes developed a smaller, rounded script that enabled them to speed up the writing process. This script was called miniscule, kind of like a Mini-Me version of majuscule (except with several letter-shape variations).
Scribes didn’t mix majuscule and miniscule at first, but they realized that capital letters attracted the eye. So, they used ornate majuscule letters in the first word on every page and to begin new paragraphs. Capital letters really “CAP”-tivated attention.

Also, I heard that spaces were not used while writing the text earlier. I Don't remember for which language was it.
So I tried to check upon this, and found out that capital letters are used in which languages and in which languages they're not used. I was able to check for 50 to 65 languages. Here is the list. I am not putting the languages one after comma, but putting them one after the other.

African: Capital letters are used.
Albanian: Capital letters are used
Arabic: Capital letters not used.
Armenian: Capital letters not used.
Azerbaijani (latin): Capital letters are used.
Bangla: Probably no.
Basque: Yes.
Belarusian: No capital letters.
Bosnian (Latin): Yes
Bulgarian: No
Burmese: No
Catalan: Capital letters are used.
Cebuano: Capital letters are used.
Chichewa: Capital letters are used.
Chinese: Capital letters not used.
Creole Haiti: Capital letters are used.
Croatian: Capital letters are used.
Czech: Capital letters are used.
Danish: Capital letters are used.
Dutch: Capital letters are used.
English: Capital letters are used. All of us know. Right?
Esperanto: Capital letters are used.
Estonian: Capital letters are used.
Finnish: Capital letters are used.
French: Capital letters are used. Also, alphabets like á é í ó ú are used.
Galician: Capital letters are used.
German: Capital letters are used.
Georgian: Capital letters are not used.
Greek: Capital letters are not used.
Gujarati: Capital letters are not used.
Hebrew: Capital letters are not used.
Hindi: No capital letters are used. However, we have things like Halant, which makes the word a bit longer, and Nukta. We use spaces like other languages, and rest of the things are same as other languages I guess.
Hmong: Capital letters are used.
Hungarian: Capital letters are used.
Icelandic: Capital letters are used.
Igbo: Capital letters are used.
Indonesian: Capital letters are used.
Irish: Capital letters are used.
Italian: Capital letters are used.
Japanese: Capital letters are not used.
Javanese: Capital letters are used.
Kannada: Capital letters are not used.
Kazakh: Capital letters are not used.
Khmer: Capital letters are not used.
Kiswahili: Capital letters are used.
Korean: Capital letters are not used.
Lao: Capital letters are not used.
Latin: Capital letters are used.
Latvian: Capital letters are used.
Lithuanian: Capital letters are used.
Macedonian: Capital letters are not used.
Malagasy: Capital letters are used.
Malay: Capital letters are used.
Malayalam: Capital letters are not used.
Maltese: Capital letters are used.
Maori: Capital letters are used.
Marathi: Capital letters are not used.
Mongolian: Capital letters are not used.
Nepali: Capital letters are not used.
Norwegian Bokmål: Capital letters are used.
Persian: No capital letters are used.
Polish: Capital letters are used.
Portuguese: Capital letters are used. Acute accent is common in the language. Test: Olá. Eu espero que você esteja bem. Estou bem obrigado. Hello. How are you I am fine thanks. ê and á letters are used.
Punjabi: Capital letters are not used.
Romanian: Capital letters are used.
Russian: Capital letters are used.
Serbian (Latin): Capital letters are not used.
Sesotho: Capital letters are used.
Sinhala: Capital letters are not used.
Slovak: Capital letters are used.
Slovenian: Capital letters are used.
Somali: Capital letters are used.
Spanish: Capital letters are used. All the alphabets are same, but one more letter is used and that is, Ñ,. Español.
Swedish. Capital letters are used.
Tagalog: Capital letters are used.
Telugu: Capital letters are not used.
Tamil: Capital letters are not used.
Turkish: Capital letters are used.
Ukrainian: Capital letters are not used.
Urdu: Capital letters are not used.
Vietnamese: Capital letters are used.

@post 15, Actually the capitalisation of nouns in German doesn't have to do by and large with the desire of someone who developed these rules to ease the destinction of the position of nouns in a sentence; it is in fact, something that had to do with the writing of the Bible in German. If one wants to distinguish the position of a noun in a sentence in German, he/she can do it without capitalisation. It is also for this reason why they invented so many words which makes the acquisition of the German vocabulary tremendously hard. If you're learning English, you're not really learning a language of the Germanic family. German has and has not at the same time anything to do with the English language. If you take many words that are common across Latin-bassed languages, you will find that only a small minority of those words have entered the German language.

English is absolutely a Germanic language. You can tell because most of the basic words are solidly Germanic. Old English, or Anglo-Saxon, borrowed a lot of Latin, it's true, but if you saw it, it would look a lot more like German. Here's some, so you can see it.

Ur byþ anmod ond oferhyrned,
felafrecne deor, feohteþ mid hornum
mære morstapa; þæt is modig wuht.

Here's some Middle English, which was the successor to Old English.

Nightes when I wende and wake,
Forthy min wonges waxeth won;
Levedy, all for thine sake
Longinge is ylent me on.
In world nis non so witer mon
That al hire bounte telle con;
Hire swire is whittore then the swon,
And feirest may in towne.

Early Modern English is Shakespeare or the King James Bible, for example. Middle English was the start of a lot more Latin borrowing, via Norman French. That's because Norman French was the language of the nobility and law, as opposed to Old English, which was the language of the common people conquered by the Normans. Old English in particular had cases, like German. Nowadays most cases are gone, except for whom and a few other words. But note that Early Modern English thou is the equivalent of Ger. du. The verbs even worked the same, e.g. thou runnest, du rennst. English has certainly borrowed from a lot of other languages. But the base of it, which includes a lot of words and the grammar, are completely Germanic.

@20, can you elaborate more on that? I can't see many similarities between English and German besides nouns/adjective position or some uncommon grammatical structures.
So if we take the sentence: He is a highly talented actor, which in German is Er ist ein hochtalentierter Schauspieler, where can you see the similarities which are specific only to these two languages besides noun/adjective rule?
We can take this sentence: I didn't go to the university because it was closed. In German: Ich bin nicht zur Universität gegangen, weil die geschlossen war. If we literally translate this sentence from German, it is I haven't to university gone because it closed was, which is completely unnatural to say.
I can think of very few grammatical structures in English, for instance it is correct to say, although it is uncommon, I'm not sure if the shop open is. In German that would be: Ich bin mir nicht sicher, ob der Laden geöffnet ist.
There are also suffixes which are borrowed from German, such as /Un/, as in unfriendly (unfreundlich).
It is however true that the origin of the English language is Germanic, since many words which stand for the very basic and most fundamental organisation of society which was family, have preserved their German origin, such as in Father, mother, brother, sister, grandparents, Uncle, but it has anyway evolved to a point where it could be highly disputed if the base is Latin or Germanic, provided that we didn't have the historic facts.

The Latin alphabet wasn't influenced by Egyptian hieroglyphics, or if it was, it was incredibly indirect. The alphabet as we know it is typically understood to go back to a Semitic language, Phoenician to be exact.

Re:  English as a Germanic language

You really have to go back to Old English to see this. For instance, German verbs don't do infinitives like we do, "to eat", they have endings, essen, gehen. Actually so far as I know the only ending is -en. In Old English, you had two endings, e.g. etan to eat, gan to go, or ascian to ask, interestingly, axian was also to ask and aks was an accepted verb in literary English until, I believe, the 17--s. I think, though I'm not a hundred percent certain about this, that the different verbal endings had to do with strong and weak verbs, -an was for strong verbs and -ian was for weak verbs. Weak verbs are regular, e.g. he asks, he asked. Strong verbs change, he is going, he went.

Like modern German, Old English had cases. These are changes that occur in nouns when they do certain things, which are too complicated to get into unless somebody really wants me to. So the basic word for stone in Old English was stan, but it might become stanum in certain situations. Stone is stein in German, there's a vowel change but otherwise, it's the same word. Similarly, Eng. for, Ger. vor. German people feel free to correct me because my German was years ago, I can't find an online dictionary, and I've also started learning Pennsylvania Deitsch which is its own dialect.

Old English also did compound words, like modern German. For instance, the Old English verse I posted previously was a verse from the Old English Rune Poem. In it we see the words oferhyrned, lit. overhorned, i.e. it has really big horns, and morstapa, lit. moor -stepper. A lot of the basic words we use are of Germanic origin. For example in that last sentence we have a, lot, of, the, words, we, are.

Some things are obscured by pronunciation or spelling changes. For instance, ship comes from Old English scip, the initial 'sc' was prounced 'sh', like Ger. 'sch'. Knight is from OE cniht, the initial 'c' sound was pronounced and always hard. This still occurs in German, e.g. Knipe. I'm not up enough on Anglo-Saxon or German grammar to compare the two, but suffice to say, our grammar is solidly Germanic.  Hope this helps, and bother me with further questions. If I don't know, I'll see if I can do some research and find out, all of this is off the top of my head mostly.