No, the Defender didn't come with a roll cage, at least not most of them. The American-spec versions that were imported for three years in the 90's had factory-supplied Safety Devices cages but most rest-of-world (ROW) Defenders did not.
Source: I am the co-founder of NAS-ROW, the Defender forum. https://nas-row.com
Source: I am the co-founder of NAS-ROW, the Defender forum. https://nas-row.com