Key issues that defined the period include:[1][2] On 29 December 1874, General Arsenio Martínez Campos's pronunciamiento overthrew the First Spanish Republic and restored the monarchy, crowning Alfonso XII, son of the exiled Isabella II, as king.

In 1898, the Spanish–American War led to the loss of Spain's last major overseas colonies, including Cuba, Guam, Puerto Rico, and the Philippines.

This event marked the beginning of the country's decline, giving rise to numerous conflicting opposition movements at local and national levels.

In 1909, failed attempts to conquer Morocco led to domestic discontent, culminating in a revolt known as the Semana Tragica in Barcelona.

The rebellion, led mainly by lower-class citizens and supported by anarchists, communists, and republicans, was a response to what they saw as unfair practices in recruiting soldiers.

The government declared a state of war and sent in troops to put down the uprising, which resulted in more than a hundred deaths and the execution of the anarchist educator Francisco Ferrer.

This led to lowered morale among the military, who felt misunderstood as they were ordered to advance inland without adequate resources to occupy the difficult terrain.

Military and civil unrest grew, amplified by fears of anarchist terrorism or proletarian revolution and the rise of nationalist movements.

On 13 September 1923, Miguel Primo de Rivera, Captain General of Catalonia, staged a coup d'état and deposed Prime Minister Manuel García Prieto after issuing a manifesto blaming Spain's problems on the parliamentary system.

[11] Alfonso XIII attempted to gradually restore the previous system and bolster his prestige by enlisting General Dámaso Berenguer as Prime Minister.

However, due to the king's perceived support of the dictatorship, this proved unsuccessful and led to growing calls for the establishment of a republic.