The Lower Brule Sioux Tribe in South Dakota this week announced it bought Westrock Group Inc., a New York-based financial services firm that includes an independent broker-dealer. Westrock becomes the industry's first financial services firm to be wholly owned by a Native-American tribe.

Michael Jandreau, the tribe's chairman, said his group bought Westrock to diversify its revenue stream and to participate directly in the U.S. capital markets. Westrock has 150 employees among its three business groups-Westrock Advisors, Westrock Institutional Group and Westrock Asset Management. The company has roughly $1.4 billion in assets under management.

With the deal, Westrock is thought to be one of the largest minority-owned financial services firms in country. It will continue to operate as an independent broker-dealer, and daily operations and management will remain unchanged.

One new twist will be the creation of a tribal services advisory group that will provide financial advisory services to both the Lower Brule Sioux Tribe and other tribes around the country. That unit will be led by Gavin Clarkson and Dennis Ickes. Clarkson, a member of the Choctaw Nation, is an associate professor at the University of Houston Law Center with a research focus that includes tribal economic development and finance. Ickes is a long-time advisor to the Lower Brule Sioux Tribe.

The tribe's main economic activities are construction and agriculture. The tribe says its farm corporation is one of the country's biggest popcorn producers.