Assuming I had some position of power, I would convert my farmland to big fields which all my villagers would work with new seed drills that I can remember how to make from a Richard Hammond program (

), Invent electricity with some lead/copper/brine and impress the king of the day by making his court jester twitch uncontrolably (making sure to get my friendly local priest to bless my 'tehpopeisteh1337' device to avoid a nasty burning at the stake). I think I would then proceed to try and fashion my own magnets if I could (I suspect this would be harder than it sounds), and create a mini power station powered by the local river (which incidentally, would now require all new toilet areas to be downstream of the drinking areas). With this new electricity, I would run massive iron beams (I'm assuming this is all I can get hold of) to the village blacksmith, who would become the first aluminium smelter in the land. With my new aluminium I would build an aluminium curtain around my land, and maybe someone elses land too, and create new aluminium weapons (damn, can't remember what that stuff you are supposed to alloy it with is called). I would then use these to attempt a military coo, which would have course be successful because of my close links with the pope. I would then usher in a new era of technological advance, in which England would be shut of from the rest of the world for a decade or two perfecting all sorts of science, so when I revealed England to the world later on, we had liek fighter planes and stuff, maybe some tanks too. I would conquer the whole of western europe, and after decontamination every sailor (to avoid killing the poor locals) ships would go and explore, setting up colonies everywhere. Soon there would be an 'electricity mill' by every river and people would have lightbulbs, and early cars would be powered by a really rubbish version of a fuel cell. I would then obviously unite the world, crush the rebels, and usher in a new age of prosperity and technological advance so great that hopefully gene therapies to combat ageing would be available from ye olde village medical dispensary, so I would live to be 2000. Soon my rockets would reach mars, and possibly adbuct some aliens from alpha proxima in the late 1700's. Population would be controlled by neutering anyone with undesirable genetic traits, thus breeding a master race of 7ft tall lean muscular citizens, many of whom would be involved in building the large hadron smasher in the 1600's, which would subsequently reveal the existence of a 'great auk' particle. My mind would gradually be integrated into a computer system, as would everyone elses eventually, so by the year 2000 everyone would be plugged into 'the OcUKrix' where they would work, learn, invent etc, and then unplug to go home and enjoy the beautiful paradise that my avoidance of the steam age brought about. Unfortunately, in the year 3345, my brain would be accidentally be deleted by an over zealous efficiency programmer. From here on in everything goes to pot: some idiot discovers oil, and within 100 years of my death, my master race has reduced themselves to scavaging in the ruins of civilization for survival. Luckily, only 1000 years later, they sort it all out, and go on to limit each persons life to 60 years, plant colonys throughout the universe, and generally annoy aliens by making sarcastic comments at every intergalactic conference.
^lol.