The English language has quite an interesting history. It was actually formed as a creole of Old English and Old French after the invasion from the Normans in 1066. Old English itself branched off of Anglo Frisian and bears a relationship to Old Saxon, which branched off of Old Germanic. However, there were some merging between tribes, like Jutes, Angles and Saxons and of course some influences from Vikings. But all of these languages are moderately similar as they are Germanic (Norse is just 'North Germanic'). So Old English is considered to be a Germanic language.
Thanks to the battle of 1066 we ended up with a Norman nobility. This meant the language of the 'common man' and the nobles were very different so they kinda met half way linguistically in that the two picked up words to communicate (hence creole). It's why we end up with different words for animals when they're walking around alive and sat dead on our plate. The explanation I was given was that the natives would raise the animals and the nobles would eat them. So we get our words like cow, chicken, sheep and deer from native words and we get beef, poultry, mutton and venison from ouour invaders. I don't know if they were the actual words, but they have their origin there.
But our adventure didn't end there. With Christianity coming over we picked up Latin, which helped influence our language more. Then of course there's language change over time to consider - language evolves as people use it. The language varied region to region and people from opposite ends of the country would speak and write differently. This is why they ended up trying to standardise the language to keep it consistent and there came the invention of the dictionary and also the printing press. As you probably well can tell it didn't take over the language as a whole, it just gave us a means of communicating effectively. We still have quite a large range of dialects and some of them I can't even understand. With the British Empire and us trying to take over the world, many languages have had their influences. Heck words come in through trade, like the word 'Kiosk', it's a Turkish word.
America also had a phase of standardisation, they wanted to correct some of the irregularities and make it more logical, but it didn't get very far and it was destined to develop its own dialects of American English, a guy from Texas will speak different to a guy from California. But it is the explanation as to why we write "colour" and Americans write "color", the 'u' does absolutely nothing to how you pronounce it.
If you are interested in reading up on the History of the English language there is actually a decent book to read by Melvyn Bragg (BBC Radio 4 Presenter), it's an interesting read. It's called The Adventure of English.
I learned a lot of this stuff studying English Language in 6th form and doing Creative Writing at University. I personally love the topic.
Now another internet language topic is that of Proto-Indo European (AKA PIE). It suggests that all Indo-European languages have a common ancestor, but it is going back so far it's hard to get a clear idea of what such a language would sound like, but there is a project to try and figure out what the language would have been like. An easy comparison to show how these languages are related is the word 'father':
Pitha - Sanskrit
Pater - Latin
Padre - Spanish
Vater - German
Father - English
Pere - French
F?ður - Old Norse (pronounced Fothur)
Here's a diagram of the evolution from PIE:http://upload.wikimedia.org/wikipedia/commons/4/4f/IndoEuropeanTree.svg