What, Freisien? You might but I doubt it! You'd get a few words though. Nor would you be likely even to understand 12th century English. The English are Germans that invaded Britain in several waves, the Angles, Jutes, Saxons and finally the Normans. The first three brought primarily old german languages and effectively erased the Celtic Brythonic language spoken in what is now called England. The Normans were also Germanic, but had settled in the north of France and spoke a sort of bastardised romantic language that was a combination of their old low norse and a romantic language resembling modern French. They invaded later and England had a two tier language system where the commoners spoke English and the Nobles spoke French (neither understandable to a modern speaker of either) Some Brythonic words remained behind but the only real remnant of that language left is the tendency to use modifiers in english, though some of that is from French as well. ('gh' 'th'and so on are mostly Celtic) You should be able to find some Chaucer on line, which is the first English language bit of fiction that is known to us. It's called Canterbury Tales and it is based on a popular and very similar Italian book of the period. You'll see from that how likely it is you might be able to understand someone speaking early English. Make sure you don't google a modern translation. Friesen is removed a few steps further, but would be closer now to modern Dutch or German. Both of those languages are still very close to English and English is still categorized as a Germanic language. Here's a page from a Friesen English dictionary http://www.allezhop.de/frysk/diction.htm
