Data on peace agreements and mediation efforts provides important insights into changing trends in international involvement in peacemaking. Across the mediation field, data shows diversification of third parties involved in peace processes and, in places, potential for congestion. Both these trends are contributing to an increasingly fragmented mediation space.

Involvement of third parties – actors not directly involved in the fighting – takes various forms, from hosting and providing material support for negotiations, to offering incentives for talks such as aid or investment, providing good offices, facilitating talks, mediating, witnessing, or signing a peace accord, guaranteeing some level of security to the negotiating sides, or supporting implementation of agreements. Different third parties get involved in different ways and at various stages of peacemaking. They are also involved in different types of agreements. Increasing diversification brings new constellations of third parties cooperating and competing with each other, a development we see as key to understanding the future of international peacemaking.

The PA-X Peace Agreement database, which collects all formal, written, and signed agreements in armed conflicts and violent crises since 1990, enables analysis of third-party signatories of agreements. Its comprehensiveness means that it is a strong indicator of trends of who is involved when agreements are reached. This work is complemented by a growing Global Peacemaking Database following all third-party mediation attempts, including those not leading to formal agreements. What follows are a few highlights drawing on PA-X, and on the cases of Sudan and South Sudan in the Global Peacemaking Database:

• Half of formal and signed agreements involve international third-party signatories – primarily states, and international and regional organisations, but also various non-state actors and individuals.
• The most prolific international third-party signatories between 1990 and 2022 were the UN (383 agreements), Russia (132 agreements), the US (126 agreements), the African Union (123 agreements) and the European Union (106 agreements).
• The engagement of Western states as third-party signatories has been decreasing over the last 15–20 years – notably France, Norway, the United Kingdom and the United States. The drop in US engagement is the starkest.
• This decline is offset by an increase in other third-party signatories – states such as Kenya, Qatar and Türkiye, and organisations like the Intergovernmental Authority on Development (IGAD) in East Africa, often in relation to agreements in their neighbourhoods.
• China’s rising global influence does not yet show an overall increase in acting as a third-party signatory, but there are indications that its interest in conflict mediation may be growing (see article by Yun Sun). Besides engagements in its neighbourhood, China also appears as the only non-African and non-Western state among top 15 mediators of South Sudanese crises since the country’s independence in 2011, predominantly engaging as a member of multilateral initiatives.
• Russia has three main types of involvement as a third-party signatory. First, like the other permanent members of the UN Security Council, it participates in large international conferences and in Security Council resolutions that function as peace agreements. These are now in decline. Second, it acts as a third party in protracted conflicts related to the dissolution of the USSR. In that, its role resembles that of a regional power. And third, over the last decade, Russia increasingly acts as a signatory to agreements related to conflicts in Syria and, reflecting its increased engagements in Africa, the Central African Republic.
• Fluctuations in frequency of individual actors as signatories are likely linked to the apparent decline of large-scale international peace conferences, a broader reduction in the overall number of comprehensive formal peace agreements aiming to resolve the entirety of a conflict, and an increase in local agreements that aim to tackle geographically limited or issue-specific aspects of the wider conflict. Western countries mostly sign comprehensive agreements, and so the drop in the number of Western signatories may not indicate their ‘retreat’ from acting as third parties, but rather a continuing level of willingness to act but fewer opportunities to do so.
• Global fragmentation seems to be influencing the drop in conflict-wide comprehensive agreements, with multiple actors mediating but hardly speaking with a unified voice. Mediation efforts in Sudan between 1990 and 2022 have seen a growth in the number of third parties and disconnected mediation efforts. After President Omer al-Bashir’s ouster in 2019, there was a three-fold increase in mediation attempts compared to the height of the Darfur crisis (2003–05), and significantly more third-party involvement (over 70 actors in 2020). In comparison, there were 15 actors involved in mediation between 2003 and 2005 (if we remove those actors only appearing as signatories of the 2004 Conclusion of IGAD Negotiations on Peace in the Sudan). Data suggest mediation in Sudan has correspondingly become less coordinated as the number of third parties has grown.
• Regional actors tend to seek opportunities to act as mediators and brokers of partial and local agreements when conflict-wide accords seem unreachable. Since 2004, data shows a clear increase in regional engagement by the AU, EU, IGAD and regional states.
• Qatar first appeared as a third-party signatory to an agreement reached between Eritrea and Sudan in 1999. Since then, it has served as third party signatory to 21 agreements, with frequency increasing since 2010 – from peace negotiations in Darfur, to multilateral negotiations for Afghanistan, Syria and Libya (see article by Sultan Barakat). Qatar often acts as a host, with five agreements named after its capital, Doha. Forty per cent of agreements signed by Qatar relate to Sudan. In Sudan, until 2011, only Qatar appeared besides African and Western states among top 15 mediators; since then, it has been joined by the United Arab Emirates and Saudi Arabia. After the outbreak of conflict in April 2023, the latter played an important role alongside the US and, from October 2023, IGAD (also participating on behalf of the AU), in Jeddah talks.
• Neighbouring states take increasingly important roles as peace brokers. Kenya’s history as a third-party signatory dates back to the early 1990s. Its involvement has remained largely regional, supporting mediation processes in Sudan and South Sudan, Uganda, Burundi, Ethiopia, Somalia and the Great Lakes region. Its 2023 agreement to lead a multinational security mission in Haiti represents an exceptional involvement in peace and security beyond the African continent. South Sudan has emerged as one of the top mediators of the Sudan crisis post-al-Bashir. South Sudan, therefore, not only provides an illustrative example of neighbourly mediation in the Horn of Africa, but also offers a rare case study of mediation by an actor that seceded from the country whose conflict it is mediating.

This article draws on the PAX Peace Agreement Database and the Global Peacemaking Database, and the following papers: Sanja Badanjak (2023) Third parties in peace agreements: first look at new data and key trends, PeaceRep, University of Edinburgh; and Mateja Peter and Kasia Houghton (2023) Congestion and diversification of third-party mediation in Sudan and South Sudan: first look at some longer-term trends. PeaceRep, University of Edinburgh. More details on peacerep.org.