At that time grenadiers were chosen from the strongest and largest soldiers. By the 18th century, dedicated grenade throwing of this sort was no longer relevant, but grenadiers were still chosen for being the most physically powerful soldiers and would lead assaults in the field of battle. Grenadiers would also often lead the storming of fortification breaches in siege warfare, although this role was more usually fulfilled by all-arm units of volunteers called forlorn hopes, and might also be fulfilled by sappers or pioneers.