"bring together," c.1600, from French rallier, from Old French ralier "reassemble, unite again," from re- "again" (see re-) + alier "unite" (see ally (v.)). Intransitive meaning "pull together hastily, recover order, revive, rouse" is from 1660s. Related: Rallied; rallying. Rally round the flag (1862) is a line from popular American Civil War song "Battle Cry of Freedom."
Most of the works drivers of the 1950s were amateurs, paid little or nothing, reimbursed their expenses and given bonuses for winning (although there were certainly exceptions, such as the Grand Prix drivers who were brought in for some events). Then in 1960 came arguably the first rallying superstar (and one of the first to be paid to rally full-time), Sweden's Erik Carlsson, driving for Saab.