The first movie shot entirely in Los Angeles was "In the Power of the Sultan," filmed May 8-9, 1909, according to this 1949 Times feature on actor Hobart Bosworth.
Or was it?

The generally accepted lore is that the first film shot entirely in Los Angeles was made on the site of a Chinese laundry on Olive Street between 7th and 8th Streets. The name is usually given as Sing Loo’s laundry. However, Bob Birchard thoughtfully wrote in last year noting that the actual name was Sing Kee‘s laundry.

A 1940 Times feature also gives the date of May 8-9, 1909.

Medved, the public relations director for Fandango, says he would like to stage a celebration to commemorate the event. The question is which date to commemorate, because, as you might expect, more than one has come down to us through the years. For example, in 1928 (at left), Hollywood marked the 20th anniversary of the establishment of the first studio in Los Angeles using the date of March 4, 1908.

The conflicting dates are enough to make one’s head hurt, especially when a little more digging turns up this 1923 article and photo, which shows a rooftop set, supposedly on Main Street, with the date of 1908, although the article refers to May 1909.

And just to complicate things, a 1929 Times article calls "Across the Divide" the first movie shot entirely in Los Angeles, filmed on Olive Street with a date of Feb. 4, 1908.

Finally, just to make things thoroughly troublesome, here’s a bit of a 1909
map of Los Angeles, showing Olive between 7th and 8th. And in case you
are wondering, the map’s list of laundries doesn’t include anything on
Olive.

In hopes of getting definitive answers, I sent an inquiry to the Autry National Center because Bosworth donated many of his movie items to the Southwest Museum, which has since merged with the Autry. I also sent an inquiry to the Margaret Herrick Library at the Academy of Motion Picture Arts and Sciences, which has records from the Selig Polyscope Co. and some Bosworth material. Let’s see what we find out. Surely there is some place in downtown Los Angeles that should have a piece of metal on it noting its place in movie history.