This is Belle S. Spafford. She was the General Relief Society President from 1945 to 1974.
She was the longest serving President in that organization’s history. Well known in both religious and secular life she was President for six different Prophets.
As well as being a strong leader for the church, working with the leadership to help the people in war torn Europe after World War 2. She also served on different international agencies, including a term as president of the National Council of Women of the United States 1968-70 as well as eight years as vice president.
As well she was a member of the National Advisory Committee to the White House Conference on Aging. These roles provided a national and international face on the organization and was seen as a benefit to the church.
President Spafford was also an accomplished writer. She worked as editor and contributor to the Relief Society Magazine and wrote two books of her own later in her life.
Her role as church leader saw the Relief Society change into an open society for all LDS women over the age of 18. During her tenure the Society grew from 100,000 to over a million. Also the interweaving of the Relief Society into the Ward budgets and the end of the dues for the Sisters was another major change under her leadership.
BYU Devotional Speech in 1975.
Ensign article on her life from 2006.
University of Utah biographical sketch