"1861 Treaty" . . . "Lagos Treaty of Cession in 1861" . . "annexed" . . . . "The Lagos Treaty of Cession" . . . "Treaty of 1861" . . . "enforced treaty in August 1861" . "British annexation of Lagos in 1861" . . "August 1861" . "1861 Treaty of Cession" . "Lagos Treaty of Cession" . "Lagos Treaty of Cession" . "annexed by the British" . . . "United Kingdom" . "British conquest" .