Conquest took place gradually, and the Europeans suffered repeated setbacks. A massive Mapuche insurrection that began in 1553 resulted in Valdivia's death and the destruction of many of the colony's principal settlements. Subsequent major insurrections took place in 1598 and in 1655. Each time the Mapuche and other native groups revolted, the southern border of the colony was driven northward. The abolition of slavery by the Spanish crown in 1683 was done in recognition that enslaving the Mapuche intensified resistance rather than cowing them into submission. Despite royal prohibitions, relations remained strained from continual colonialist interference.