Flag of the first Empire of Brazil, with 19 stars.It gained 20 stars only in 1853, after the creation of the Paraná province.). 
 Vexillology and heradic in the molds of this book, an official publication of the government of Brazil, on page 74 and others. The shield conforms to the one at the base of the Crown of Pedro I of Brazil in 1822 which is the continental format also referred to as neoclassical: .
Governo do Império do Brasil
Governo do Império do Brasil/Jean Baptist-Debret