The Germanic branch of the Indo-European family has an interesting history of its own. Germanic languages have some features that other Indo-European languages do not. Furthermore, this branch has some features in common with certain other, otherwise-unrelated branches of that family. Thus, it's something of an anomaly within the IE family. Recently scholars have determined the reasons for this: As the original people who spoke Proto-Indo-European (the hypothetical original language from which all the other IE languages descended) began to drift apart and migrate to different places, those who eventually spoke Proto-Germanic (the hypothetical descendant of Proto-IE from which all the Germanic languages descended) meandered somewhat around the southern steppes of modern Russia, into the northern Balkans, and then into central Europe. This caused them to pass by, or through, peoples speaking various other branches of IE; in this way, Proto-Germanic picked up various features of others. As migrations continued, these peoples drifted further apart, leaving us the linguistic "jigsaw puzzle" we find today.
Around classical times (i.e. the early Roman Imperial period), Proto-Germanic had itself already broken up into three main "versions" — North Germanic, West Germanic, and East Germanic. It's unclear whether or not these three languages were merely dialects, and therefore mutually intelligible. It's likely that they were, to some extent, very similar to each other.
East Germanic was best known to the Romans, as it was spoken by the Goths (the Ostrogoths and Visigoths) who attacked and ultimately toppled the western Roman Empire. We are lucky to have a significant, surviving document written in the Gothic language (properly known as Old High Gothic) — a copy of the Bible translated into that language by a man known as Wulfila or Ulfilas. While this Gothic Bible doesn't provide a complete picture of the Gothic language, it is undoubtedly as close as we will ever get to the Proto-Germanic language.
As the Imperial period passed and the "Dark Ages" began, the three versions of Germanic diverged further, as each Germanic group migrated apart. The North Germans went into the north — Scandinavia. The Eastern Germans, the two Gothic tribes, settled in former Imperial territory (Italy, Iberia, and Illyria). The Western Germans — including the Franks and Saxons — settled in western Europe, mainly modern France and Germany. Migrations among these tribes continued, and they shuffled about quite a bit, as other invaders (the Huns, Avars, and later the Magyars) came in from the east.
The Angles and Saxons, therefore, wound up in what is now northwestern Germany, and occupied the same region. They blended into a single nation, the Anglo-Saxons. At about the same time, they began setting out across the North Sea in raiding parties, attacking the southeastern coast of Britain. Eventually their incursions overwhelmed the native Celts and the remnants of the Romans left behind after the Empire evacuated the island. Eastern Britain belonged to them, and they established a kingdom of their own there.
The Anglo-Saxons were converted to Christianity by the natives of Britain, however, and fortunately for us, began recording chronicles in their own language. Documents from that time period are numerous, and the Anglo-Saxon language is now well-known and understood. Enough of it is known that it could, conceivably, be used for everyday conversation (barring the necessary invention of new words for things like modern technology — which is readily possible since Anglo-Saxon allows for compounding). Later Anglo-Saxon is also known as Old English, and was spoken in Britain for some five centuries or so.
Significantly, Old High Gothic shows many features in common with Anglo-Saxon/Old English, and speakers of these languages could likely have understood each other with only a little trouble.
The establishment of an Anglo-Saxon, or English, kingdom in Britain, left the native Celts in the west of the island (Wales and Cornwall) and the Picts in the north (Scotland). They were the pre-eminent power of the island, and their language dominated (even some of the Celts and Picts learned it).
Old French itself was primarily a Romance, or Latin-based, language, but had been heavily influenced by the original language of the Franks. It had little in common with Old English — in spite of the fact that both had roots in the West Germanic branch of the IE language family. Initially, the aristocracy, imported from Normandy and other parts of France, spoke Old French, and the rest continued speaking Old English.
This socially-stratified language separation didn't last long, however, as it made communication between them nearly impossible. Since the English had numbers on their side, it was English which prevailed — but a great many words of French (and thus Romance) origin entered the language. By the time of Chaucer, in the 13th century, the people of England spoke pretty much a single language (with, of course, a few regional and societal variations). This single language is known as Middle English.
For this reason, while Middle English has many similarities to modern English, and speakers of modern English can learn to read Middle English with little trouble, they sound quite different from each other, when spoken.
The English of Shakespeare is known as Early Modern English, since it had pretty much settled into its modern form. People nowadays have some trouble with Shakespeare, mostly because he wrote in verse, and in an artistic manner. The "vernacular", or common language, of his day, however, was very much like what is spoken in England, now, and if you heard someone speaking it on the street, you'd have little trouble understanding them.
Unlike most IE languages, however, the system of inflection in English isn't complex. Grammatical function is conveyed more often by word order rather than by inflection. In some ways, this makes English somewhat inefficient. For example, in Latin, one could say the phrase "I love" in only one word — amo — rather than two. But this makes expressions simpler, since it's unnecessary to master a huge variety of verb forms and endings. This creates efficiencies in different ways, which more than make up for the need to include words which, in other languages, were only implied.
Furthermore, the lexicon, or word-base, of English, comes from two branches of the IE family — from the Germanic, via Anglo-Saxon, and from the Romance, via Old French. English has a lexicon of nearly half a million words — more than any other language. Each of these words has subtleties of meaning, or connotations, which allow one to express ideas in a highly refined manner. Ambiguities are far less common in English than in other languages. It also adds to the efficiency of English. For this reason you will often find that the same text, expressed in several languages, requires the fewest words, when in English.
Finally, like all Germanic-branch languages, English has liberal compounding rules, which make it easy to create new words, as the need arises. English has kept up rather easily with new technology, and in fact, is an excellent language to use to convey technical knowledge of any kind.
No, my point is simply that English has a unique history, which has led it down a unique path. Among the languages of the world, it has many peculiarities.