The House of Bourbon replaced the House of Habsburg in Spain in 1700, and introduced economic reforms that gradually began to revive trade in Santo Domingo. The crown progressively relaxed the rigid controls and restrictions on commerce between Spain and the colonies and among the colonies. The last ''flotas'' sailed in 1737; the monopoly port system was abolished shortly thereafter. By the middle of the century, the population was bolstered by emigration from the Canary Islands, resettling the northern part of the colony and planting tobacco in the Cibao Valley, and importation of slaves was renewed.