The Feast of the Cross had its origin at Jerusalem, and is connected with the commemoration of the Finding of the Cross and the building, by Constantine, of churches upon the sites of the Holy Sepulchre and Calvary.

In 335 the dedication of these churches was celebrated with great solemnity. This dedication took place on the 13th and 14th of September.  It lasted eight days. In Jerusalem, then, this feast bore an entirely local character. It passed, like so many other feasts, to Constantinople and thence to Rome.

The 3rd of May was called the feast of the Finding of the Cross, and it commemorated in a special manner Saint Helena's discovery of the sacred wood of the Cross.