However , on 13 May Cromwell launched a night attack .
Major White was sent by Cromwell and Thomas Fairfax to mediate with Thompson 's troops and give assurances that force would not be used against them .
On 13 May Cromwell launched a night attack .
Major White was sent by Cromwell and Thomas Fairfax to mediate with Thompson 's troops and give assurances that force would not be used against them .