In Summer of 2185, at high noon, Jacob and Marcus (a super mutant) crossed paths many, many miles southwest of Broken Hills and punched and shot each other for a few days, each unable to get an advantage over the other. Eventually, they realized the pointlessness of their fight, and broke down in joined laughter, beginning a strong friendship between them. The two started traveling together, arguing over the Master's failed plans for the Wasteland and the Brotherhood doctrine and whether or not the Master could truly neurolink his biology into the Cathedral computer network.
As they wandered through the wastes, they attracted a following of other refugees from the war, who believed that Marcus's strength and Jacob's power armor gave them the closest thing available to safety. In Fall of the same year, Marcus and Jacob, along with the trail of ghouls, humans, and super mutants, founded the community of Broken Hills.
In Spring of 2186, Jacob said goodbye to Marcus, and moved on for parts unknown. Marcus went on to found another safe haven for super mutants in the Mojave Wasteland, and named it Jacobstown to honor the memory of his old friend. Jacob the Chemist was also named after him.