Though little is known of Steward's early life, he became more involved with the labor movement while working twelve hours a day as a machinist's apprentice.
He would go on to use this working experience as a means to garner sympathy and credibility in the movement while speaking at labor union meetings, taking part in strikes and publishing pamphlets.
On the recommendation of Steward, the Machinists' and Blacksmiths' Union (to which he belonged) sent resolutions to the Boston Trades' Assembly, urging for a concentration on reduction of hours for working individuals.
Not satisfied with the efforts of the Boston Trades' Assembly in approaching the issue, Steward joined several other former Machinists' and Blacksmiths' Union members in forming the Labor Reform Association, which in 1865 would be reconstituted into the Grand Eight Hour League of Massachusetts.
In reaction to a shift of emphasis that he saw as detrimental to the cause (from working hours to monetary issues), Steward served on the arrangements committee of the short-lived New England Labor Reform League, which split into two separate movements.