Ambrogio Spinola had captured Oldenzaal in 1605 and Groenlo a year later – with this the region was under Spanish occupation and they undertook raids. In May 1626, the Dutch decided to eliminate the Spanish from the area once and for all. They brought two armies under the command of Frederick Henry, Prince of Orange and with them a detachment of the English army which had been raised as result of their war with Spain. Oldenzaal's garrison which had been continuously strengthened since it capture and twenty years later the city had around 800 troops along with cannon under the command of Spanish Governor Guillermo Verdugo.
