What is an actionist?

The term "actionist" refers to a stock speculator, particularly in the 18th century in the Netherlands. This was the time of large financial bubbles, such as those surrounding the shares of the South Sea Company and the Mississippi Company. Actionists were involved in the rapid buying and selling of shares, which often led to extreme price fluctuations and ultimately to the bursting of these bubbles. The term is also associated with earlier speculative episodes such as the Tulip Mania.