How did the Secular Franciscan Order begin?

The Secular Franciscan Order began with Saint Francis of Assisi. From the very beginning of his ministry Saint Francis found people who desired to follow his way of life and spirituality — yet were married or did not want to become religious. Saint Francis responded by writing “The First Letter to all the Faithful” around 1215. So many people wanted to follow Saint Francis that the Rule of the Secular Franciscans was approved in 1221 — at that time, they were call the Brothers and Sisters of Penance later called the Third Order of St. Francis. One of the earliest Secular Franciscans was Lady Jacoba de Settesoli who was present when Saint Francis died in 1226.  From this Order the Third Order Regulars (T.O.R.) emerged in the 15th century. The Order continued as the Third Order of St. Francis, Secular. In 1978, its name was changed to the Secular Franciscan Order (SFO). In 2011, the acronym changed from SFO to OFS (Ordo Franciscanus Saecularis or Order of Secular Franciscans).