This song appeared in the Gazette Politique et Commerciale d’Haïti on 22 November 1804. The version I have is from a publication by the Bibliothèque National d’Haïti of the first two years of the newspaper.
In a lot of ways, the song reminds me of the Hymne Haitiène that was performed in January 1804. Both songs draw on French revolutionary traditions in their tune; the Hymne Haitiène is to the tune of the Marseillaise while Couplets is to the tune of the vaudeville in the Devin du Village (a play by Jean-Jacques Rousseau). But, at the same time as they draw on this tradition, they are both vehemently anti-French and anti-slavery. Couplets explicitly names the “vile slavery” whereas the Hymne Haitiène frequently references “liberty.” Anti-slavery and Anti-French sentiments, or “Liberty and Independence,” are the key factors of the end of the revolution (or, the “war of independence” 1802-1804) and of the early independence period. Both songs also pay tribute to Dessalines’s personal role in securing national independence and individual liberty in Haiti. A really interesting aspect in both songs is the description of Dessalines as the “father” of the country and of Haitian citizens as his “children.” The characterization of the population as a family might have been an attempt to unite a very divided population (something that Dessalines also tried to do through a series of violent massacres in the early months of 1804). He clearly struggled with the creation of “nation” but these songs suggest that he deployed a number of different tactics to achieve this goal. I would also add his 1805 constitution to this series of attempts to create an “imagined community.”
Here is my translation of Couplets, any corrections and additional interpretations are welcome!
Sung and performed for His Majesty Jacques 1st
Emperor of Haiti
By C. Cezar Télémaque, comptroller[?] of the Northern Department.
Tune: The Vaudeville from Devin du Village
Sing, celebrate our glory,
Friends of the island of Haiti;
March, support our victory
The well-being of our country;
He who gives us happiness;
Long live the Emperor.
It was he who punished the arrogance
Of the French, our true enemies;
And by his sweet mercy,
Made subjects and friends[?];
Always cherish, etc..
His name, his valor, his courage,
Terrifies all of the schemers[?];
Enemy of the vile slavery;
He sees us as his children;
Always cherish, etc.
Receive from me the sweet[?] gratitude[?]
My respectable Sovereign;
That God inspires you with wise laws,
And protects you with his hand;
I always cherish
He who gives me true happiness
Long live the Emperor.
 I make this argument in a forthcoming chapter in an edited volume on 19th century anti-slavery movements; Julia Gaffield, “’Liberté, Indépendance’: Haitian Anti-slavery and National Independence,” A Global History of Anti-Slavery Politics in the Nineteenth Century, edited by William Mulligan and Maurice Bric (London: Palgrave MacMillan, forthcoming May 2013).
 I discuss this aspect in further detail in: Julia Gaffield, “The Complexities of Imagining Haiti: A Study of National Constitutions, 1801-1807,” Journal of Social History, (2007) 41(1): 81-103.