Lyonel Tyrell

"Daeron the First succeeded at great cost and reigned in Dorne for a few glorious months. One night, his steward pulled down and sash by his bed to summon his consorts. Instead, the canopy split open and a hundred red scorpions fell on him. He wa a Tyrell, you would think he was used to getting stung."

- Prince Oberyn Martell

Lyonel Tyrell is an unseen character in Game of Thrones. He is not expected to appear, being long dead by the time it begins.

History
Lyonel participated in the Conquest of Dorne and was declared Steward of Dorne by King Daeron I Targaryen, the Young Dragon. He was murdered, however, when he pulled down a sash by his bed to summon his consort and a hundred red scorpions fell on him. His death ignited a revolt that led to the death of Daeron and the end of the Iron Throne occupation.

In the books
In the A Song of Ice and Fire novels, Lyonel Tyrell was an infant during the Dance of the Dragons, with his mother ruling the Reach as Regent. She chose to remain neutral during the civil war, thus the Reach was divided between the supporters of Aegon II and those of Rhaenyra.

Decades later, Lyonel commanded the army that invaded Dorne via Prince's Pass. After the Young Dragon's initial victory, Daeron appointed Lyonel as governor of Dorne. The Dornishmen however proved cunning and impossible to rule, particularly under a Reachman - the Reach and Dorne having been bitter enemies for centuries. Thus, Lord Lyonel moved with his train from one keep to the next, chasing rebels out and keeping the knees of the Dornishmen bent. It was his custom to turn the lords of the keeps he stayed in out of their chambers and sleep in their place. One night at Sandstone, seat of House Qorgyle, finding himself in a bed with a heavy velvet canopy, he pulled a sash near the pillows to summon a wench. When he did so, the canopy opened and a hundred red scorpions fell upon him. His death sparked new revolts, and in a fortnight all the work of the Young Dragon was undone, eventually bringing the about the death of King Daeron himself.