Complex sentence: The maps were produced in the "Atlas of the Counties of England and Wales" published in 1579, the first atlas of any country and it contained 35 maps, each bearing the arms of Elizabeth I and Thomas Seckford Saxton's patron.
Split into simpler sentences: The maps were produced in the "Atlas of the Counties of England and Wales" published in 1579, the first atlas of any country. It contained 35 maps, each bearing the arms of Elizabeth I and Thomas Seckford, Saxton's patron.