Excerpts from Books and Wikipedia
Capital at Hattusas was sacked and abandoned; Possibly attacked by "Sea Peoples"; [1177 BC, Kindle, Location 2465] "The great powers of the day—the Hittites, the Mycenaeans, the Canaanites, the Cypriots, and others—fell one by one." [1177 B.C., Kindle, Location 240] "Although Egypt under Ramses III was the only major power to successfully resist the onslaught of the Sea Peoples, New Kingdom Egypt was never the same again afterward . . . Egypt became a second-rate empire; a mere shadow of what it had once been." [1177 BC, Kindle, Location 364] "The city was destroyed, together with the Hittite state itself, around 1200 BC, as part of the Bronze Age collapse. Excavations suggest that Hattusa was gradually abandoned over a period of several decades as the Hittite empire disintegrated." [Wikipedia: Hattusas]