The Honor Guard, or 'avwl' batlh, were a military unit of Klingon bodyguards that served to protect the Emperor of the Klingon Empire as well as the Chancellor of the High Council of the Klingon Empire and even the many councilors.
The Honor Guard were first created during the Mythic Age when the rebel band known as the Hand of Flame were recruited by Kahless the Unforgettable in his battle against the tyrant Molor. The leaders of the group; namely O'gat, Kollus and To'Kar were given the task of training Kahless's army.
After the victory against Molor, the three masters of the Hand of the Flame pledged their loyalty to Kahless and he helped them form the Schools of Great Warriors training facilities. These would train a new generation of warriors that were the elite of the Klingon military and the best of which would be chosen to protect the Emperor and the High Council from threats. (TNG video game: Klingon Honor Guard)
- The exact relation between the Honor Guard and the Yan-Isleth (which has a similar function) -- even as to whether they are truly separate organizations -- has been left unspecified.