AUGUSTA, KAS. — Patrick H. Thiessen, a retired flour milling executive, died March 7 in Augusta, Kas. He was 91.

A native of Hutchinson, Kas., Mr. Thiessen graduated with undergraduate and law degrees from the University of Kansas, Lawrence. While at K.U., he met Lorraine (Larry) Ross. The two wed in 1950 and were married nearly 62 years, until her death in 2012. After graduating from law school, Mr. Thiessen was commissioned a first lieutenant in the U.S. Army Judge Advocate General Corps. He worked at the Pentagon in the Defense Appellate Division.

For several years after his military service, Mr. Thiessen practiced law in Kansas, first in Salina and then Hutchinson, and he was elected Reno County Attorney in 1958.

Two years later, Mr. Thiessen moved with his family to Wichita and joined the flour milling business of Ross Industries, Inc. Ross was a major Kansas milling business established in 1918 by Mr. Thiessen’s father-in-law Paul Ross and other members of the Ross family. Mr. Thiessen worked in the offices of Kansas Milling Co., Wichita, the largest of five businesses that made up Ross Industries (the others were American Flours, Newton, Kas.; Hunter Milling Co., Wellington, Kas.; Wichita Terminal Elevator, Wichita, Kas; and Whitewater Flour Mills, Whitewater, Kas.).

Ross Industries was acquired by Cargill in 1974. Cargill expanded rapidly in milling while Mr. Thiessen was there, combining into a single milling business its Burrus Milling and Ross Industries businesses with the North American milling business of Seaboard Allied Milling Corp., acquired in the early 1980s. During his time with Cargill, Mr. Thiessen was manager for the Southwest Region of Cargill Flour Milling.

He was active in the North American Millers’ Association (formerly Millers National Federation), chairing the group’s export committee during a period of active U.S. flour exports. He was named a lifetime M.N.F. member following his retirement.

Mr. Thiessen was elected to the Wichita School Board and was its president in 1969. He was a member of the board of elders for Eastminster Presbyterian Church and for 25 years was a director of Intrust Bank.

In addition to his wife, Mr. Thiessen was preceded in death by his sister, Lillian Love. He is survived by four children: Mark Thiessen, Evan Thiessen Stumpf, Chris Thiessen McDonnold, Anne Thiessen Owen; eight grandchildren and five great-grandchildren.

Memorial services were private. In lieu of flowers, memorials may be sent to a charitable organization of the donor’s choice.