According to www.latvia-usa.org, the Embassy of Latvia offically relocated here on December 1st, 2005, with a ribbon cutting ceremony attended by the Latvian President and the Mayor of Washington DC on March 1st, 2006.
From http://www.culturaltourismdc.org:
Seemingly out of place among the avenue's grand homes is the one-time studio and home of philanthropist and socialite Alice Pike Barney. Built in 1902 by the prolific Washington architect Waddy Wood, the Spanish Mission style of Barney Studio House, the first house to be built on the circle, is an interesting departure from Wood's more conservative works. (You will see other homes by Waddy Wood as you continue this tour.) In this romantic setting, Barney's celebrated salon hosted a dazzling array of Washington artists and literati between 1902 and 1924. The sculptured reclining woman that you see in front recalls her patronage of the arts.
Recently purchased by the Latvian Embassy, Barney's Studio House is undergoing extensive restorations. When completed, the public will be permitted inside to see the first two floors.