The Legion of Mary is an organization of lay Catholics and religious leaders who are inspired to serve Jesus though, with and in Mary, who is in union with Jesus. Mary’s will is the will of God in Jesus. Legion of Mary was founded on 7th September 1921 in Dublin Ireland.
In Uganda, Legion of Mary was spread by Venerable Edel Quinn who arrived in Uganda on 22nd July 1938 from Ireland in her mission to East and Central Africa. She was welcomed by the MillHill Fathers and the Little Sisters of St. Francis of Assisi at Nsambya.
First Praesidium
The first Praesidium was started on Saturday, 24th September 1938 at Holy Ghost Normal school in Nkokonjeru in the present Nkokonjeru Parish, Lugazi Diocese.
The Praesidium was called “Our Lady of Mercy” because 24th September 1938 was her Feast. The first work allocated was church mending and hospital visitation just like the first Praesidium in Ireland.
The very first officers of the first Praesidium were:
| Yoanina Namakula | President |
| Rose Namatovu | Vice President |
| Virizini Namagembe | Secretary |
| Maria Namuddu | Treasurer |
Senatus of Uganda
Senatus of Uganda was birthed from the then Kampala Comitium that was under the Senatus of East Africa.
The inauguration happened on Sunday, 20th May 1962 in a meeting that was attended by representatives from the Concilium and the Archbishop, His Grace Joseph Nakabaale Kiwanuka among others.
The first Officers of the Senatus of Uganda were:
| Name | Office |
| Rev. Fr. T. Agostori | Spiritual Director |
| Br. Raphael Owor | President |
| Br. T. Fernandes | Vice President |
| Br. G. Albuquerques | Secretary |
| Sr. J. Gracias (Elected in June) | 1st Asst. Secretary |
| Br. L. Komakech (Elected in August) | 2nd Asst. Secretary |
| Sr. E. Mukasa | Treasurer |
The first meeting place of the Senatus was NorthCote Hall, Makerere University.