I have done a search through the online database at "Voyageur Contracts Database," La Societe historique de Saint-Boniface, and found a few men named Beaulieu during a simple search -- that is, enter surname and see what pops up.
Let's see what we have:
Boucherville Beaulieu family:
Amable Beaulieu of the Boucherville Beaulieus signed a contract in 1758 to go to Detroit;
Pierre Beaulieu from Boucherville signed up in 1758 to go to Detroit.
A Military man?
Bazyle (fils) Parmier dit Beaulieu from Montreal St-[eloy?] signed up in 1754 to go the Poste des Miamis for Francois marie piquote de Bel Estre Ecuyer lieutenant d'infanterie (was he in the infantry?).
This family is the Palmier Beaulieu -- see Palmier Beaulieu Family Tree at Ancestry.ca -- and even though I do not have a Bazil Palmier dit Beaulieu in this tree, there are later members bearing this name in Illinois. He must be their ancestor.
Andre Beaulieu dit Laport from Prairie de Lamagdeleine entered the fur trade in Montreal in 1751 to travel as Voyageur to Michilmackinac;
Estinne [sic] Beaulieu dit St-Denis entered the fur trade in 1743 from Paroisse de Saint Michel, as a Garcon [boy] voyageur going to Michilimackinac;
Etienne Beaulieu entered the fur trade in 1747 from St-Sulpice to go to Poste de Ounepigon [Winnipeg post perhaps?] as a winterer;
Jean-Baptiste Beaulieu from La Cote St-Michel, Montreal, signed on in 1733 to go "into the north" with Marin Hurtubise et Compagnie;
Louis Beaulieu from Montreal signed on in 1790 to go to the dependencies in the South;
Joseph Beaulieu from Vercheres signed on in 1803 for the "Departement de la Riviere au Bombinge" via Michilimakinac, Kamanistiguia au Portage de la Montagne, for the company of McTavish, Frobisher & Co. -- he could be the voyageur who accompanied David Thompson except that there was a Beaulieu in the Red River district in 1801;
Joseph Beaulieu from St. Laurent signed on in 1774 as a Garcon [boy] voyageur for the Mississippi with the company Lambert St. Omer;
Francois Beaulieu from Pot au Beur Sorell (Sorel), signed on with Alexander Mackenzie's Company in 1803 for three years -- and I am going to have to translate the notes at the bottom because I can read enough French to see that it talks of "home of his father Francois, voisin le Gros Bellevalle......"
Jacques Beaulieu from Quebec (City?) signed in 1795 to go "dans le Nord" or into the North, with McTavish, Frobisher & Co.
Ambroise Beaulieu from Montreal signed a contract in 1822 to go to Lac des Sables as a winterer for the HBCompany;
Ambroise Beaulieu from Montreal re-entered [?] the fur trade in 1826 in Montreal, for one year; apparently not working for the HBC but Day & McGillvary?
Ambroise Beaulieu from Montreal entered the fur trade in 1827 to travel to Lac des Sables as a voyageur;
Charles Beaulieu from St-Roch-de-l'Achigan entered the fur trade in 1800 to travel to Detroit;
Bazile Beaulieu (perhaps one of the Hudon dit Beaulieus) from Maskinonge, entered the fur trade in 1807 to go to Fort Kaministiguia (Lake Superior);
Francois Beaulieu from Pointe a la Calliere entered the North West Company in 1815;
Francois Beaulieu from Fauxbourg Ste. Anne enter the fur trade in 1818, working for the Compagnie du McTavish, McGillivrays & Co. [North West Company];
Francois Beaulieu from Petit Maska (Yamaska), entered the fur trade in 1818 as a winterer;
Francois Beaulieu from Varennes signed on in 1817 to go to Michilimackinac;
Henry Beaulieu from Maskinongay signed on in 1816 to go to Michilimackinac and the North West dependencies for McTavish, McGillivrays (otherwise the North West Company);
Paul Beaulieu from Masquinonge signed on in 1808 to go to Michilimackin et depenceies, L'Isle St. Joseph and the Mississippi with Mess. de la Compagnie de Michilimackinac; he signed up again in 1811;
Clement Hudon dit Beaulieu, from Fauxbourgh, Quebec, signed up in 1818 for 3 years to go to Michilimackinac with Charpentier et Menuisier;
Paul Hudon dit Beaulieu from Riviere du Loup signed up for a year in 1812 to go to Michilimackinac with Compagnie de Michilimackinac; he signed up for a second time in 1813 for same place.
I don't think a quick look at this database has helped us identify our Beaulieu brothers, but I never expected it would.
But there is another Beaulieu family I am quite interested in, and I will speak of this family in my next posting.
Following that, I will consider the Beaulieu men who might have reached David Thompson's Kootenais district without actually coming across the mountains with David Thompson -- that means abandoning every single theory I have presented so far and looking at a new theory.
But that's what you have to do, sometimes, to find out how your ancestors got where they got.