Fairly recently--it was actually put together in the span of a few months. The script was translated by a team of 5 Navajo in 36 hours, auditions for roles took place in the Navajo Nation over the May the Fourth weekend, and it was screened on the 4th of July. THAT'S efficiency!
They originally only had a limited printing of 1500 DVDs, sold only at the Navajo Nation Museum gift shop, and they sold out in one weekend. (Since there are over 170,000 people living inside the Nation, that's not really a surprise.) Just a few weeks ago, the Navajo Nation, Wal-Mart and Fox struck a deal to reprint the DVD and distribute it in about 30 Wal-Marts on and near the Rez, so I had a copy shipped from Arizona to my local Wal-Mart.