The Organization of the Petroleum Exporting Countries is an intergovernmental organization of 14 nations, founded on 14 September 1960 in Baghdad by the first five members, and headquartered since 1965 in Vienna, Austria. As of September 2018, the then 14 member countries accounted for an estimated 44 percent of global oil production and 81.5 percent of the world's "proven" oil reserves, giving OPEC a major influence on global oil prices that were previously determined by the so-called "Seven Si The Organization of the Petroleum Exporting Countries (OPEC) was founded in Baghdad, Iraq, with the signing of an agreement in September 1960 by five countries namely Islamic Republic of Iran, Iraq, Kuwait, Saudi Arabia and Venezuela.