南岬之盟是台湾清领时期斯卡罗与美国于十九世纪共同订立的外交条约。
公元1867年美籍商船罗发号(the Rover)在台东外海触礁，当时船长杭特（Joseph W. Hunt）偕夫人还有生还船员共14人仓皇逃生，在垦丁附近上岸。但不慎闯入屏东的斯卡罗王国领土，被视为侵略者而遭出草，史称罗发号事件。
美国政府向清帝国抗议，时任台湾兵备道吴大廷得知此事，说：“台地生番穴处猱居，不载版图，为声教所不及，今该船遭风，误陷绝地，为思虑防范所不到，苟可尽力搜捕，无不飞速檄行，无烦合众国兵力相帮办理。”意思是，台湾从枋寮到鹅銮鼻这一区是当地斯卡罗王国领土，不属大清国管辖。然而，引发美国强烈不满。
愤怒的美国政府态度更加强硬。至此清廷政府才发觉事态严重，遣台湾总兵刘明灯调查此事。美国代表不满清廷处理，于是决定自行与南排湾十八社代表谈判，1867年10月，在恒春东门东方三公里处，古名叫火山的地方订立盟约，称之为“南岬之盟”。内容要求外国人没事不可上岸，海难登陆人员须举红旗为号否则格杀勿论。
南岬之盟的双方代表，美方方面，当时人在北京的林肯总统好友、美国驻华公使蒲安臣，决定派出的美国外交人员是驻厦门领事李仙得 (Charles W. le Gendre)，而台湾方面，斯卡罗王国派出的缔约代表是斯卡罗国王卓杞笃。出席者主要有美国领事李仙得、英国通译必麒麟、琅峤汉人、清廷台湾兵备道吴大廷、台湾镇总兵刘明灯。南岬之盟结束之后，刘明灯勒石于车城庄福德庙（今福安宫），即俗称“刘提督碑”。但是李仙得在北京的上级并不承认此盟约。
1869年2月，美国政府因为清廷曾声明南排湾不受清廷的管辖，自行再派代表签订书面“亲善合约”，建筑灯塔，并保证日后不再杀害西洋船舶海难人员等等。此亲善条约便成为美国与台湾斯卡罗王国原住民双方直接签订的“国际条约”，美国国务卿给国会的年度报告收录此条约，据传此条约尚存于美国国会图书馆及屏东旭海。
Village of the Sabarees, February 28, 1869
At the request of Tauketok, the ruler of the eighteen tribes south of Liangkiau, and between the range of hills east of it and the Eastern Sea including the bay known as the Southern Bay of Formosa where the crew of the American bark Rover were murdered by the Koaluts, I, Charles W. Le Gendre, United States consul for Amoy and Formosa give this as a memorandum of the understanding arrived at between myself and the said Tauketok in 1867, the same having been approved by the United States Government and assented to, I believe by the foreign ministers at Pekin viz:
Cast-aways will be kindly treated by any of the eighteen tribes under Tauketok. If possible, they are to display a red flag before landing.
Ballast and water. - Vessels requiring supplies are to send a crew on shore, displaying a red flag, and must not land until a similar token has been shown from the shore, and then only at the spot indicated. They are not to visit the hills and villages, but, when possible, are to confine their visit to the Tuiahsockang, being the first stream on the east coast north of the southeastern cape of South Bay, and to the Toapangnack, to the west of the rock where the Rover's crew were murdered, the latter being the better watering place in the northeast monsoon. Persons landing under other than these conditions do so at their own peril, and must not look, I believe, for protection from their government if molested by the natives, who in such case will not be held responsible for their safety.
CHAS. W. LE GENDRE, United States Consul.
Witness: I. ALEX. MAN, Commissioner of Customs for Southern Formosa.
Witness and interpreter: W. A. PICKERING
