Julius Caesar invades Britain twice during his Gallic Wars, in 55 and 54 BCE.

The first invasion, made late in summer, is either intended as a full invasion (in which case it is unsuccessful - it gains a beachhead on the coast of Kent but achieved little else) or a reconnaissance-in-force expedition.

The second is more successful, setting up a friendly king, Mandubracius, and forcing the submission of his rival, Cassivellaunus, although no territory is conquered and held for Rome, but is restored to the allied Trinovantes, along with promised tribute of other tribes in eastern England.