Endeavour

I have just found the following instance of "endeavour" used as an active verb, in Dryden's translation of Maimbourg's *History of the League*, 1684. "On the one side the majestique House of Bourbon,... and on the other side, that of two eminent families which endeavour'd their own advancement by its destruction; the one is already debas'd to the lowest degree, and the other almost reduc'd to nothing." —p. 3.