The greatest foreign exchange earner for Nigeria before the advent of petroleum was

Before the discovery and commercial exploitation of petroleum in the late 1950s and 1960s, agriculture was Nigeria's greatest foreign exchange earner. The agricultural sector dominated the Nigerian economy and was the backbone of export revenue.

Nigeria's major agricultural exports during this period included:

• Cocoa - primarily from the Western Region (now southwestern Nigeria)
• Groundnuts (peanuts) - from the Northern Region
• Palm oil and palm kernels - from the Eastern Region
• Rubber - from the Mid-Western Region
• Cotton - from the Northern Region

These cash crops were exported in large quantities to Europe and other international markets, generating the bulk of Nigeria's foreign exchange. Each region of the country had marketing boards that coordinated the purchase and export of these commodities.

The other sectors were relatively minor foreign exchange earners: handicrafts were produced largely for local consumption, mining (of tin and columbite) contributed some export revenue but far less than agriculture, and manufacturing was in its infancy and largely import-dependent rather than export-oriented.