Simplify the following text for a Grade 13 native English-speaking person.
Original: Before nationalisation of the railways in 1948 and the creation of British Railways , three of the `` Big Four '' railway companies operated in Northamptonshire : the London , Midland and Scottish Railway , London and North Eastern Railway and Great Western Railway .
Simplified: Before nationalisation of the railways in 1948 and the creation of British Railways ) , Northamptonshire was home to three of the `` Big Four '' railway companies ; the London , Midland and Scottish Railway , London and North Eastern Railway and Great Western Railway .