Simplify the following text for a Grade 9 native English-speaking person.
Original: The standing Navy Royal , with its own secretariat , dockyards and a permanent core of purpose-built warships , was created in the 16th century during the reign of Henry VIII .
Simplified: A permanent Royal Navy , with its own staff , dockyards and a group of purpose-built warships , was created in the 16th century in the reign of Henry VIII.221-37 Under Elizabeth I England became involved in a war with Spain .