The Sykes-Picot Agreement of May 1916, was a secret agreement that was concluded by two British and French diplomats, Sir Mark Sykes and Georges Picot. The Sykes-Picot Agreement involved itself with the partition of the Ottoman Empire once World War One had ended.
The Sykes-Picot Agreement effectively handed over control of Syria, Lebanon and Turkish Cilicia to the French and Palestine, Jordan and areas around the Persian Gulf and Baghdad to the British. While neither France nor Britain actually 'owned' these territories, they were to effectively control them at a governmental and administrative level. Northern Syria and Mesopotamia were also considered to be an area of French influence while Arabia and the Jordan Valley were considered to be a sphere of influence of the British. Jerusalem was to be governed by an international administration.
This agreement did clash with the McMahon Agreement of 1915 and the statements made by T E Lawrence to the Arabs who had expected to be allowed to govern their own regions after helping the Allies fight the Turks during World War One.
The agreement was never completely fulfilled by the peace settlements but it did lead to the Arab people not fully trusting the British or French governments at times in the future.
How did the Arab people find out about the Sykes-Picot Agreement?
After the Bolshevik Revolution in November 1917, the Communists, led by Vladimir Lenin, found a copy of the agreement in the Russian government's archives. Russia, in the agreement, was to have influence in Turkish Armenia and northern Kurdistan - hence why the pre-communist government had a copy of the agreement. The Russian Communists released the contents of the agreement into the public domain - thus explaining why numerous Arab groups knew about it.