Complex sentence: Built in 1836-1840 as a result of the July Revolution and fears of an invasion of France by Austria, the fort of Loyasse was intended to protect the city from invaders from the east.
Split into simpler sentences: Built in 1836-1840 as a result of the July Revolution and resulting fears of an invasion of France by Austria. The fort of Loyasse was intended to protect the city from invaders from the east.