The 1937 Nyon Conference established Allied naval patrols in the Mediterranean to curb submarine attacks on shipping during the Spanish Civil War, bypassing the ineffective Non-Intervention Committee.
Key Facts
- First agreement signed
- 14 September 1937
- Second agreement signed
- 17 September 1937
- Attending nations
- UK, France, Bulgaria, Egypt, Greece, Romania, Turkey, USSR, Yugoslavia
- Absent major powers
- Italy and Germany did not attend
- Italy joined patrols
- November 1937 (Tyrrhenian Sea)
- Attacks attributed to
- 'Pirates unknown' — Italy not named directly
By the Numbers
Location
Cause → Event → Consequence
During the Spanish Civil War, Italy conducted unrestricted submarine warfare against international shipping in the Mediterranean without formally declaring war. The Non-Intervention Committee and the League of Nations failed to halt these attacks, prompting Britain and France to convene an emergency diplomatic conference.
The Nyon Conference met in September 1937, producing two agreements: the first, signed on 14 September, established Anglo-French naval patrols across much of the Mediterranean to counterattack aggressive submarines; the second, three days later, extended similar provisions to surface vessels. Italy was invited to join patrols without being formally accused of the attacks.
Naval patrols largely succeeded in halting submarine attacks on merchant shipping for the remainder of the Spanish Civil War, marking a rare effective response compared to broader non-intervention efforts. However, critics noted the conference preserved the naval status quo, benefiting Franco's Nationalist forces while offering little protection to the Republican side.
Political Outcome
Two agreements established Anglo-French-led naval patrols in the Mediterranean; submarine attacks on international shipping were largely suppressed, though Italy was not formally blamed.
Mediterranean shipping vulnerable to unattributed submarine attacks; Non-Intervention Committee ineffective
Anglo-French naval patrols established; Italy joined patrols in November 1937 without formal censure