From this session interdict / Every fowl of tyrant wing, / Save the eagle, feathered king; / Keep the obsequy so strict.
-- William Shakespeare, "The Phoenix and the Turtle," 1601
Sitting there while the Baptist minister did his glib and rapid office, he (Stevens) looked around at the faces, town faces and country faces, the citizens who represented the town because the town should be represented at this obsequy…
-- William Faulkner, The Mansion, 1959
Obsequy comes from the Latin obsequium meaning "compliance, dutiful service." It's been used in English since the late 14th century.