At the dawn of the Klingon Empire, five hundred warriors assaulted the Great Hall of Qam-Chee. The city garrison was routed with only Kahless and Lukara holding their ground. They defeated the warriors and began what some considered as one of the greatest romances in Klingon history.
After they were married, the newlyweds were nearly killed by Molor's troops. In remembrance of this event, a ritual was created for the traditional Klingon wedding ceremony. In the ceremony, the bride and groom were symbolically attacked by friends and family wielding Ma'Stakas.
In 2373, after sharing a holosuite recreation of this event with Jadzia Dax and discovering his feelings for her, Worf married her. (DS9: "Looking for par'Mach in All the Wrong Places", "You Are Cordially Invited")