Identify the reasons behind britain's desire for control of the suez canal.

The Suez Canal had become one of the world's most-traveled shipping lanes.
The British wanted control of the canal to facilitate access to their trade and imperial interests in India and the Far East.

The Suez Canal was built by the French, and opened in 1869.  Great Britain became the largest stockholder in the canal in 1875 by buying up stock from the Ottoman governor of Egypt.  In 1882, Britain invaded Egypt and occupied the country for its own purposes.  Even after ending that occupation later, the British still insisted on retaining rights to the canal -- until the 1950s when Gamal Abdel Nassar, then the president of Egypt, took control of the canal for Egypt.

The ottoman empire would allow the conquered territory to follow whatever religion they wanted to follow which created less of rebellion in conquering land and forcing those to follow a different religion.