Short Answer 
From 1812 to 1820, Spain experienced a political crisis with the suspension of the Constitution of 1812 and the return of Fernando VII to absolute power, leading to the repression of liberal reforms. This era, known as the ‘D‚àö¬Æcada Ominosa’, featured political oppression and insurrections in Spanish colonies seeking independence amidst a weakened government.
Step 1: Understanding the Context of 1812 to 1820
During the years from 1812 to 1820, Spain faced a political crisis characterized by the suspension of the Constitution of 1812, also known as ‘La Pepa’. This period was marked by the return of Fernando VII to absolute power after his control by the French during the War of Independence against Napoleon. The significance of this time lies in the stark absence of constitutional governance and liberal reforms.
Step 2: The Role of the Constitution of 1812
The Constitution of 1812, enacted by the Cortes de C√°diz, introduced major reforms aimed at establishing national sovereignty, the separation of powers, and freedom of the press. However, upon his return in 1814, Fernando VII abolished this constitution, rejecting all liberal reforms. This act effectively set the stage for a restoration of absolutism, leading to widespread political repression.
Step 3: Consequences and the “D‚àö¬Æcada Ominosa”
This period is referred to as the ‘D‚àö¬Æcada Ominosa’ due to the reassertion of absolutism and the persecution of liberals striving for constitutional reforms. During these years, Spain also faced insurrections and independence movements in its American colonies, as various territories sought autonomy and independence in the turmoil caused by the weakened Spanish government.