You can look up the basics at Wikipedia or read this history of Tiki Bars, or visit Critiki – "A Worldwide Guide to over 600 Tiki Bars, Polynesian Restaurants and other sites of interest to the midcentury Polynesian Pop enthusiast." Or you can visit The Purple Orchid on Richmond Street in El Segundo, for your fix of Polynesian kitsch.
They're still around, with "Tiki god" masks and all. Have a Sumatra Kula, Zombie or a Mai Tai. A lot of the drinks come with the little paper cocktail umbrella, or so one hopes.
Blame Los Angeles – the first Tiki Bar opened here in 1933, Don the Beachcomber. That was Ernest Gantt, bringing a bit from his travels in the South Pacific to LA in the Depression. That eventually turned into a chain of sixteen restaurants.
After the war Gantt moved to Hawaii and opened the be-all-and-end-all of Tiki bars, Waikiki Beach, the one with the myna bird that was trained to shout "Give me a beer, stupid!" That was on the beach of course, with Tiki torches and all, not like this place, a few blocks west of a giant oil refinery.
It's all irony now. And Trader Vic's is pretty much gone too – Trump closed the one at the Plaza and the flagship Beverly Hills operation closed. Ah well, some Tiki bars live on, as self-referential inside jokes.