[2] A memorial brass in St Mary's Church, Swansea, erected to the memory of Johnys and his wife Maud, records that he fought under John, Emperor of Constantinople, for five years against the Turks and Saracens "in the p[ar]tis of troy grecie and turky", and was knighted at the Holy Sepulchre in Jerusalem on 14 August 1441.
The brass records that afterwards he was Knight Marshal of France for five years under John, Duke of Somerset, and became at a later date Knight Marshal of England under John, Duke of Norfolk, who gave Johnys the Manor of Landimore in Gower.
[1][3][4] After the Duke of Norfolk's death in 1461, William Herbert, 1st Earl of Pembroke took over as custodian of Gower, and it is thought that Johnys during the 1460s was involved in the upbringing of Lord Herbert's ward Henry Tudor, later Henry VII.
[1] Johnys's first wife Mary is mentioned in 1451; her parents and date of death are unknown.
[1][3] In December 1468, Edward IV appointed Johnys as one of the Poor Knights of Windsor; it is supposed that Maud had died by this time.