Succession Crisis of 1185–1186

Also known as Coup of Sibylla and Guy

The bitter factional struggle that followed the deaths of the leper king Baldwin IV and the boy-king Baldwin V — and the chaotic coronation that handed the kingdom to Guy of Lusignan a year before Hattin.

The death of the leper king Baldwin IV in 1185 left the throne to his eight-year-old nephew Baldwin V, with Raymond III of Tripoli as regent and Joscelin III of Courtenay as the boy's guardian. The arrangement masked a deeper rift: a Court Party led by Baldwin's mother Agnes of Courtenay and her son-in-law Guy of Lusignan against a Barons' Party led by Raymond III and the Ibelins.

When Baldwin V died unexpectedly in the summer of 1186 the crisis broke into the open. Sibylla and Guy, supported by the patriarch Heraclius, the masters of the Templars and Hospitallers, and Joscelin III, slipped into Jerusalem behind a sympathetic faction and had Sibylla crowned alone — whereupon she immediately set the royal crown on her husband's head. Raymond III, marshalling the rest of the barons at Nablus, attempted to crown Sibylla's half-sister Isabella I instead, but the plan collapsed when Isabella's young husband Humphrey IV of Toron refused to play the king and slipped away to do homage to Guy.

The kingdom was so divided after the coronation that Raymond III initially refused to acknowledge Guy at all, and even negotiated a separate truce with Saladin from his lordship of Tiberias. The internal rift contributed directly to the lack of strategic coordination on the eve of Hattin in 1187: when the Frankish field army marched east to its destruction, it was a kingdom that had not yet finished its civil war.

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