It seems like there was war between the Romulan and Klingon Empires between TOS and TNG. The Romulans and Klingons were allies at the end of TOS, but seems like some time after TOS that alliance fell apart and the Klingons and Romulans became enemies. I would assume that after the Romulans launching a sneak attack on Khitomer, that Klingons would declare war on the Romulan Empire.
The Romulans also attacked a Klingon outpost on Narendra III, so it seemed like there was a state of war between the Klingons and the Romulans.
So what happened, how did this war end? I think Klingons would want to strike a really great blow against the Romulan Empire, after the Khitomer attack, the Klingons went to war with the Federation for far less, but for some reason the war stopped with no clear winner. Were both sides so easily matched that no side could could really achieve a great victory over the other side? Did they ever sign a cease fire, because I assume there was never a peace treaty between the two sides.