The Borg incursion of 2366-2367 was the first attempt by the Borg Collective to assimilate the United Federation of Planets. The incursion was instigated by a single Borg cube which left a trail of destruction on its way to its primary target, Earth. During the incursion Captain Jean-Luc Picard was assimilated and transformed into the Borg speaker Locutus. (TNG episode: "The Best of Both Worlds"; TOS novel: The Return)