In 1922, Dartiguenave was replaced by Louis Borno, who ruled without a legislature until 1930. That same year, General John H. Russell, Jr., was appointed High Commissioner. The Borno-Russel dictatorship oversaw the expansion of the economy, building over of road, establishing an automatic telephone exchange, modernizing the nation's port facilities, and establishing a public health service. Sisal was introduced to Haiti, and sugar and cotton became significant exports. However, efforts to develop commercial agriculture had limited success, in part because much of Haiti's labor force was employed at seasonal work in the more established sugar industries of Cuba and the Dominican Republic. An estimated 30,000–40,000 Haitian laborers, known as "braceros", went annually to the Oriente Province of Cuba between 1913 and 1931. Most Haitians continued to resent the loss of sovereignty. At the forefront of opposition among the educated elite was "L'Union Patriotique," which established ties with opponents of the occupation in the US itself, in particular the National Association for the Advancement of Colored People (NAACP).