France and Spain begin to blockade southern Vietnam, in a punitive
campaign designed to revenge the Vietnamese execution of three
Jesuit missionaries the previous year. In the event, the campaign
continues until 1862, and ends with the establishment of the French
colony of Cochinchina.
Citation:
Editors. "Franco-Spanish blockade of Cochin-China begins".
The Literary Encyclopedia. First published 30 December 2011
[http://www.litencyc.com/php/stopics.php?rec=true&UID=18361, accessed 19 June 2013.]