The Strange Boundaries of Equatorial Guinea

March 2, 2020
Marissa Wood


Equatorial Guinea is a small central African state that is made up of a series of islands and a mainland territory. The islands are spread out throughout the eastern Gulf of Guinea, the largest of which is Bioko, located just off the coast of Cameroon, followed by Annobón to the southwest of São Tomé and Príncipe, and then Corisco and Elobey Islands located closer to the mainland. Continental Equatorial Guinea is referred to as Río Muni.

An overview map of Equatorial Guinea, showing both its continental territory known as Rio Muni along with its islands of Bioko and Annobon.
Equatorial Guinea extends beyond continental Río Muni. It also consists of Bioko, Annobón, and several smaller islands.

The modern-day African state was formerly a loosely controlled Spanish colony before gaining independence in 1968. If you’re interested in colonial Equatorial Guinea, this article gives an excellent overview. Since its independence, Equatorial Guinea has become infamous for being one of the most corrupt and repressive states in Africa, with the current president serving as Africa’s longest running dictator. Equatorial Guinea struck offshore oil wealth in the mid-1990s, and despite the economic boom, the majority of Equatorial Guineans live in abject poverty. To learn more about Equatorial Guinea’s current political status, The Guardian had some great recent coverage.

Mainland Equatorial Guinea shares land frontiers with only Cameroon and Gabon, but its various islands have both established and provisional maritime boundaries with Cameroon, Nigeria, São Tomé and Príncipe, and Gabon. Both of its land borders have differing de jure (legal) versus de facto (actual) practices, and only two of its potential maritime boundaries have been established (with Nigeria and São Tomé and Príncipe).

Land Boundaries

The land boundary between Río Muni and Cameroon was defined in vague terms between French and German colonial powers in 1885. Interestingly, Spain had such a minute presence in mainland Equatorial Guinea that France was able to claim Río Muni in its “spheres of influence” agreement. Germany at the time administered Cameroon. France would officially relinquish its claims to Río Muni in 1900. The 1885 Agreement also separated French and German claims in west Africa, including between modern-day Benin and Togo, and authorized French control of Senegal and the Gambia.

Map showing the land boundary between Equatorial Guinea and Cameroon
The 1885 land boundary extends from the Atlantic Ocean to the tripoint with Gabon. Note the de jure/de facto differences in the line.

The boundary between German Kamerun and Río Muni as defined in 1885 followed the Campo or Ntem River from its mouth in the Bight of Biafra until the river meets the 10˚ East meridian and from there the borderline is “the parallel of latitude” (no additional descriptors offered) until the 15˚ East meridian, after which French and German claims in 1885 dissolved into unknown jungle. Neither Spain and Germany, nor Spain and France, or even modern-day Equatorial Guinea and Cameroon have signed any additional boundary agreements.

Modern-day administrative practices differ from the 1885 delimitation in a few key places. First, the Campo/Ntem River is utilized as the boundary line past the 10˚ East meridian until the river takes a sharp turn to the north into Cameroon. The unspecified parallel of latitude serves as the boundary except for a slight northward deviation to the west of the Equatorial Guinean town of Ebebyín. The differences in de jure/de facto practices are not currently the source of any official boundary disputes, although Cameroon has complained at times of Equatorial Guinea’s unilateral border fencing encroaching on Cameroonian territory. The frontier desperately needs a modern demarcation but lack of funds, lack of motivation, and the likely difficulties in resolving de jure/de facto differences have stalled this process.

Equatorial Guinea’s other land boundary is similarly problematic. In the same 1900 agreement in which France officially relinquished its claim to Río Muni to Spain, a vague frontier was defined with then French Congo, modern-day Gabon. It begins in the mouth of the Muni River in the Bight of Biafra and continues along its thalweg to the Outemboni River until it first meets the 1˚ North parallel, which it then follows until the 11˚20’ East meridian which serves as the border northward until it meets the frontiers of Cameroon.

Map showing the land boundary between Equatorial Guinea and Gabon.
The 1900 land boundary between Equatorial Guinea and Gabon. Note the differences in de jure versus de facto control.

Of course, this de jure description only partially captures the story. The river boundary is utilized further to the east of its first meeting with the 1˚ North parallel, the de facto boundary extends to the north of the parallel to allow for Gabonese control of the town of Médouneu, and the Kié River functions as the operative boundary to the tripoint with Cameroon, so that the entire town of Ebebyín is administered by Equatorial Guinea.

As a brief aside, the de jure boundary versus de facto control over the town of Médouneu has been handled cartographically in a variety of ways by major web map providers. Google has proffered the most interesting solution, placing their Médouneu label on the 1˚ North boundary, when the actual town, in fact, lies to the north based on the distribution of populated places in satellite imagery. It can be frustrating when the facts on paper don’t match the facts on the ground.

Screenshot of Google Imagery showing how Médouneu is labeled below the 1 degree parallel boundary when in fact the city is to the north.
The location of Médouneu on a screenshot from Google Maps.

A Modern Frontier Delimitation?

The boundaries between Equatorial Guinea and Gabon get weirder. In 2004, Gabon submitted what it claimed to be a 1974 bilateral agreement on land and maritime frontiers with Equatorial Guinea to the United Nations. Article 2 of this agreement contains adjustments from the 1900 colonial delimitation which better adhere to current de facto practices. It also grants a series of disputed islands, Mbanié, Conga, and Cocoteros, to Gabon and defines a maritime boundary.

Fifteen days after Gabon’s submission of the 1974 agreement to the UN, Equatorial Guinea presented its first objection which was followed by two additional notes expressing concern over the validity of the agreement. Equatorial Guinea commented on the lack of original signed French and Spanish copies of the 1974 text. Additionally, despite supposedly signing an agreement, the two states continued bilateral maritime boundary negotiations from 1972 to the present. Equatorial Guinea considers the 1974 agreement a forgery with no legal basis in the definition of its land and maritime frontiers with Gabon.

In 2016, Equatorial Guinea and Gabon agreed to submit their maritime dispute to the International Court of Justice. The land boundary issues do not seem to have been included in this initial framework. Equatorial Guinea ratified the agreement in 2017, but Gabon has yet to do so and the ICJ has not been presented with the case.

Maritime Boundaries

In addition to Equatorial Guinea’s rather strange land boundaries, it has two established maritime boundaries, one in the north between Bioko and mainland Nigeria, two separate segments of boundary with São Tomé and Príncipe, one for Bioko and one for Annobón. The maritime boundary with Nigeria was established in a 2000 agreement after a decade of negotiations for which oil exploitation was a key driver. The two-part maritime boundary with São Tomé and Príncipe was established based on the principle of equidistance in 1999. None of the four potential tripoints have been officially established.

Map showing the maritime boundary between Equatorial Guinea and Nigeria
The maritime boundary between Bioko and Nigeria.

Equatorial Guinea has yet to establish an official maritime boundary with Cameroon, although the two states are in negotiations. Potential boundary delimitations with Gabon are further complicated due to the dispute over Mbanié, Conga, and Cocoteros Islands. The maritime frontier with Gabon will have a northern segment dividing the adjacent coasts of Río Muni and Gabon and a western segment for the opposite costs of Annobón Island and Gabon.

Map showing the maritime boundary between Equatorial Guinea and São Tomé and Príncipe
The maritime boundary between São Tomé and Príncipe and Annobón in the south and Río Muni and Bioko in the north.

There is much work to be done on the international land and maritime boundaries of Equatorial Guinea. The presence of hydrocarbons has driven negotiations and the establishment of maritime frontiers with São Tomé and Príncipe and Nigeria. But sorting out overlapping maritime claims and vague colonial delimitations with Cameroon and Gabon is much more complicated. In both those cases, at the minimum, a modern, complete, and bilaterally agreeable land boundary needs to be established before any real maritime negotiations can occur. A thorough demarcation would be better. This may be possible with Cameroon in the short term but is much more complicated with Gabon due to the more contentious de jure/de facto boundary issues and the dispute over Mbanié, Conga, and Cocoteros. Without an economic driver, it may be a very long time before Equatorial Guinea’s boundaries are more firmly located than those drawn up during the colonial period on old, small scale, and inaccurate maps.

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