The German victories at Southhampton and Hastings, allowed German forces to surround and create a ring around London, one similar to Soviet tactics at the First Battle of Stalingrad. The British army could only muster a force of 100,000 mostly inexperienced boys and old men from the home guard to fight against the well armed professional soldiers of the Wehrmacht. Never the less they had the fortune of a American forces of about 40,000 based in London to help in defence of the city. By the time Nazi allied forces entered the city, it was greatly defended and fortified.