Pretty girls and Rose Parade floats have been paired up for about 118 years, but here is a nifty picture from 1932. That was the year Los Angeles was set to host its first Olympiad, so "Nations and Games in Flowers" was the theme of the parade that year.
Bit o' trivia: the parade had no themes until 1918. Guess what the first theme was, that year--as the U.S. joined the Allies in WWI? Patriotism.
This picture is from the Los Angeles Public Library's online photo collection of the 1932 Olympics.
1932 was also the first year that a shortwave radio broadcast of the parade was heard--internationally, according to the official Rose Parade history. Gee, I'll be that was exciting.
Here's another picture from the 1932 parade--of Albert Einstein. This one's from the Rose Parade History Timeline.
Although he had not emigrated to the US at that time, Einstein visited CalTech in Pasadena in 1930, 1931, and 1932 as a visiting scholar. He'd already won the Nobel Prize and was a superstar; thousands of people gathered to hear him speak.