United Nations was established as the result of World War II . After the destruction of World War -I and World War -II World was thinking seriously for the establishment of an international organization which takes the responsibility of ensuring World peace . At the end of World War-I  World succeeded in creating the League of Nations but it totally failed and resulted in Second World War.  The founder of United Nations are those 26 countries  of allied nations who participated in "UN Declaration"   first official use of the term of  "United Nations", which was suggested by United States of America  President Franklin Delano Roosevelt on 1st January 1942 during Second World War.