

The college was founded on the site of the 13th century Hospital of St John in Cambridge at the suggestion of Saint John Fisher, Bishop of Rochester and chaplain to Lady Margaret. However, Lady Margaret died without having mentioned the foundation of St John's in her will, and it was largely the work of Fisher that ensured that the college was founded. He had to obtain the approval of King Henry VIII of England, the Pope through the intermediary Polydore Vergil, and the Bishop of Ely to suppress the religious hospital and convert it to a college. The college received its charter on 9 April 1511. Further complications arose in obtaining money from the estate of Lady Margaret to pay for the foundation and it was not until 22 October 1512 that a codicil was obtained in the court of the Archbishop of Canterbury. In November 1512 the Court of Chancery allowed Lady Margaret's executors to pay for the foundation of the college from her estates. When Lady Margaret's executors took over they found most of the old Hospital buildings beyond repair, but repaired and incorporated the Chapel into the new college. A kitchen and hall were added, and an imposing gate tower was constructed for the College Treasury. The doors were to be closed each day at dusk, sealing the monastic community from the outside world.
Over the course of the following five hundred years, the college expanded westwards towards the River Cam, and now has eleven courts, the most of any Oxford or Cambridge College. The first three courts are arranged in enfilade.
St John's College first admitted women in October 1981, when K. M. Wheeler was admitted to the fellowship, along with nine female graduate students. The first women undergraduates arrived a year later. college was founded on the site of the 13th century Hospital of St John in Cambridge at the suggestion of Saint John Fisher, Bishop of Rochester and chaplain to Lady Margaret. However, Lady Margaret died without having mentioned the foundation of St John's in her will, and it was largely the work of Fisher that ensured that the college was founded. He had to obtain the approval of King Henry VIII of England, the Pope through the intermediary Polydore Vergil, and the Bishop of Ely to suppress the religious hospital and convert it to a college. The college received its charter on 9 April 1511. Further complications arose in obtaining money from the estate of Lady Margaret to pay for the foundation and it was not until 22 October 1512 that a codicil was obtained in the court of the Archbishop of Canterbury. In November 1512 the Court of Chancery allowed Lady Margaret's executors to pay for the foundation of the college from her estates. When Lady Margaret's executors took over they found most of the old Hospital buildings beyond repair, but repaired and incorporated the Chapel into the new college. A kitchen and hall were added, and an imposing gate tower was constructed for the College Treasury. The doors were to be closed each day at dusk, sealing the monastic community from the outside world.
Over the course of the following five hundred years, the college expanded westwards towards the River Cam, and now has eleven courts, the most of any Oxford or Cambridge College. The first three courts are arranged in enfilade.
St John's College first admitted women in October 1981, when K. M. Wheeler was admitted to the fellowship, along with nine female graduate students. The first women undergraduates arrived a year later.