I don't know, I followed all the ride very closely, and I don't think that manipulation played that big of a role. Bitcoin was clearly undervalued at the beginning of the year, when its price was around $1,000. Bitcoin needed a protocol update, however, the community couldn't agree on how to proceed, and there was the threat of a contentious fork, where bitcoin would split in 2. In the end, the protocol update was carried out (SegWit) and while there ended up being a fork (Bitcoin Cash) it wasn't the contentious fork everybody feared.
So once that all those threats were out of the way, the price of bitcoin started climbing really fast. Korean and Japanese people started buying cryptocurrency like there was no tomorrow and the market started to overheat. Koreans wanted to buy crypto so badly, that they were paying premiums of more than 40% compared to the rest of the world. Taxi drivers in the US were promoting ICOs, EOS had huge billboards in Times Square and the euphoria that goes hand in hand with every bubble started settling in.
But everybody knew that the price growth was outpacing the increase in usage of the technology, so once the CME futures launched in December, there were no more huge news in the horizon, and the price started deflating.
So was there some kind of price manipulation going on? Probably. But looking back there is really no need for price manipulation, you can explain the price increase using any economics textbook.