Legio II Traiana Fortis, Trajan's strong legion, was a Roman legion levied by emperor Trajan in 105 AD, along with Legio XXX Ulpia Victrix, for the campaigns in Dacia. There are still records of the II Traiana Fortis in Egypt in the middle of the 5th century AD. The legion's emblem was the demi-god Hercules.
In 115 AD, Traiana Fortis was incorporated in the large army used for Trajan's Parthian Campaign. In 117, the legion was allocated in Judea, to insure peace after the rebellion that was just ending. In 125 they are sent to Egypt for the first time, to share camp in Alexandria with Legio XXII Deotariana. Between 132-136 AD they are again in Judea to deal with another revolt.
The history of II Traiana Fortis gives an example of the political role of the legions. In 194, Pescinnius Niger, governor of the province of Syria, rebels, with the legion's support, among others. His rival was Septimius Severus who would become emperor. In the days before the final battle, the legion changed sides and vowed fidelity to Severus. This would prove to be decisive for Pescinnius defeat.