According to Weyland's own account, he was a member of "a continuum of beings" who observed various universes but did nothing to help lifeforms less powerful than themselves. Visiting the universe of Cragon V, Weyland was touched by the goodness of the planet's people. Having become their ruler, he returned to his continuum to resign his membership in it. Unfortunately, while he perceived himself to be absent from Cragon V for only a few moments, months actually passed, during which the crew of the Klingon battle cruiser Ghargh visited the planet and began teaching its people how to fight.
Shortly after Weyland's return, the USS Enterprise also visited Cragon V. A fight between the Starfleet and Klingon landing parties resulted in the death of a native child. Regarding the Federation as hypocritical and therefore worse than the Klingons, Weyland punished Captain James T. Kirk by sending the other three surviving members of the landing party to eras in Earth's past drawn from their knowledge of their respective backgrounds. He transported Lieutenant Commander Hikaru Sulu to Japan in 1600, Commander Montgomery Scott to Scotland in 1746, and Lieutenant Pavel Chekov to Russia in 1942. He also rendered the engines of the Enterprise and the Ghargh inoperative, causing their orbits to begin to decay.
Pleasantly surprised by the honorable actions of Sulu, Scott and Chekov in their respective pasts, and by the willingness of Kirk and Kral, the commander of the Ghargh, to form an alliance to meet with him, Weyland eventually returned the three Starfleet officers to the Enterprise and restored control to the two ships. Kirk and Kral both reported to their respective commands that Cragon V should be avoided in the future. (TOS novel: Home is the Hunter)
Weyland's description of the "continuum" from which he comes sounds very much like the Q Continuum, but this is not explicitly confirmed.