The Original Series had a Romulan Bird of Prey, which looked nothing like the Klingon one introduced years later in Star Trek III, Search for Spock.
However, as I understand it, originally, the script for Star Trek III, Search for Spock, had it as a Romulan Bird of Prey, and that the Klingon Commander was going to steal it from the Romulans. That particular plot line, however was written out later, and it became just a Klingon Bird of Prey; thereby giving the Klingon’s cloaking technology in which they never possessed before.