refers both to a specific period of Spanish history, between the general strike of August 1917 and Primo de Rivera's coup in September 1923, and to the social phenomenon spread in many areas of Spain during which Spanish employers hired thugs to intimidate and often attack trade unionists and notable workers – and vice versa. It was characterized by the birth and proliferation of several armed groups composed of ("gunfighters"), men specialized in the use of violence.

It reached its most tragic consequences in the region of Catalonia and especially in the city of Barcelona, where hundreds of people were killed or injured as consequence of political violence and social attacks. Above all, social clashes of these years played a fundamental role in the crisis of the Spanish Liberal State, whose existence definitely finished with de Rivera's coup.

Historical background At the beginning of 20th century, Spain was led by a parliamentary monarchy, also known as Spanish Restoration regime, born in 1874 after the end of the First Spanish Republic and the Restoration of the monarchy with Alfonso XII. The political system was organized around the so-called , the alternation of the two main parties, Liberal and Conservative, and the composition of governments was decided before political elections through a negotiation process between the Ministry of the Interior, the king and local chiefs.

The Spanish Liberal State was built on three main elements: the monarchy, the Catholic Church and the army. After the death of Alfonso XII in 1885, his posthumous child Alfonso XIII became king of Spain. He reigned until the birth of the Second Spanish Republic in 1931.

At that time the Church had a big influence on Spanish society. It organized the educational system and it was in charge of several hospitals and nursing homes. After the election of Pope Pope Leo XIII in 1878 there was a warming of relations between the Spanish State and the Church and in 1883 moderate members of the Catholic Party joined the Conservative Party. This event enabled clergymen to regain support within the Spanish bourgeoisie, which at the turn of the century gained more power and influence in social and political life. Nevertheless, the ecclesiastical world was also a perfect environment for anti-liberal ideas, culminating in the formation of an integralist catholic movement towards the end of the century.

The third bastion of the regime was the army, which from the middle of the 19th century became the referee of the political life. State authorities did not manage to submit it to their control and, as a consequence, soldiers affirmed their role as defenders of the social order. Moreover, political parties used to mobilize the army every time there were strikes, civil disorders and demonstrations. This attitude increased the number of social clashes and fostered the perception that violence was an available instrument for solving social and economic issues.

Crisis factors had its roots in the crisis of the Restoration Regime, which from the end of the 19th century showed its weakness to face social and economic transformations in Spanish society. The fragility of the Spanish State, which was the consequence of internal and external factors, produced a growing social instability leading to the explosion of violence.

Industrialization and social mobilization In the last decades of 19th century Spain experienced rapid but uneven industrialization which characterized only some areas of the country, especially the Catalonia region. A lot of workers moved from rural areas to big cities such as Barcelona, Valencia and Zaragoza in order to find a job in the factories.

This situation led to important social and economic transformations. In particular, a huge concentration of workforce in limited areas facilitated the circulation of socialist and anarchist ideas and the birth of workers' associations. At the turn of the century there was a multiplication of strikes and labor protests and the number of participants and levels of intensity constantly grew in this period. In 1888 the first national trade union was founded with the name of (UGT), helping to transform strikes in an conscious strategy for collective claims. From the beginning of the 20th century social protests and strikes also spread to rural areas, especially Huesca region.

At the turn of the century the spread of strikes and trade unionism produced a sense of fear in Spanish authorities, which started to consider them as real challenges to the established order. The State's answer consisted in increasing its repressive ability, by increasing the number of police forces, such as the Civil Guard. However, it soon became clear that police and gendarmerie forces were not enough for preventing and repressing social disorders, spread throughout the country and sometimes difficult to reach due to lack of modern railways or streets.

As a consequence, authorities were forced to use more and more frequently the army, but this attitude led to the militarization of the public order. At the same time, the incapacity of the State in extending repression to remote areas encouraged the proliferation of self-defense. From the end of the 19th century several groups composed by landlords and employers started to employ violence to fight strikes and defend their properties. An example was the Requeté, a paramilitary group created by Carlists, which during 1910's fought some pitched battles against left-wing associations. This situation facilitated episodes of social clashes and stimulated the use of violence.

Military defeat

Another factor of crisis was the so-called , the military defeat during the Spanish–American War in 1898. The first consequence for Spain was the loss of her last colonies in the Caribbean Sea and in the Pacific Ocean, resulting from the emancipation of Cuba and Philippines and the acquisition of Puerto Rico and Guam island by U.S.A.

This defeat had significant impacts on the internal social order. In the immediate aftermath of the war numerous critics to politicians emerged and the idea of the necessity of a regeneration became very popular. From that moment, several social actors started to promote different strategies in order to improve or modify state institutions, including the use of political attacks (anarchists) or a military solution (sectors of the Church and parts of the bourgeoisie). At the same time, after the war, the Spanish colonial army was forced to come back in Spain and this provided the authorities with a wider military force, which from the beginning of 20th century was used in the repression, often brutal, of protests and strikes. This attitude contributed to accelerate the loss of legitimacy by civil authorities, which became dependent on the use of the army.

First World War

When the First World War broke out in 1914 the conservative government headed by Eduardo Dato decided to remain neutral and this decision was kept for all the duration of the conflict. This situation led to a big development of Spanish industrial production, due to the increased needs of raw materials and military equipment by the countries participating in the war. Thousands of workers moved to the biggest industrial areas with immediate consequences on the social order. In fact, the high number of job demands allowed the employers to reduce wages, but this decision pushed trade unions to increase protests and struggles.

Moreover, during the war there was a deterioration of working class's quality of life, because of the reduction of basic necessities imports and inflation. All these elements encouraged the multiplication of food protests, which forced the end of Dato's government in 1915. Simultaneously, the difficult situation faced by many workers, and their concentration in places where left political ideas were highly developed, facilitated the growth of labor organizations and the radicalization of trade union struggle. Overall, the war was the catalyst of all existing problems and frustrations and it produced important cracks within the Spanish society.

The origins of the conflict

From the beginning of 1916 the new government led by Álvaro Figueroa y Torres tried to minimize the impact of the war by proposing economic reforms in order to reduce the military budget and other state expenses. The failure of this attempt and the worsening of economic situation produced the fall of the government.

In June 1917, the soldiers protested against the reduction of state military budget by creating their own trade unions (). In July, the , an organization composed by members of the Catalan bourgeoisie, created a regional assembly in order to start a process of constitutional reform in opposition to the Madrid's parliament. In August, the first general strike in Spanish history was organized by UGT, with the support of (CNT), a confederation of anarchist trade unions founded in 1910.

The general strike paralyzed for some days some important Spanish cities, but it was strongly repressed by police forces and the army, in an attempt by the new government of Eduardo Dato to take advantage of the crackdown of social protests to unite the army, monarchists and the bourgeoisie. However, the brutal repression radicalized the extreme sections of CNT and encouraged them to use violence as a tool of union struggle.

Until that moment the main strategy adopted by CNT, promoted by Salvador Seguí and the union's most moderate wing, consisted of long strikes which aimed to press authorities to accept the workers' requests. However, the repression of the general strike changed the situation and some anarchists decided to create armed groups, using violence against employers and industrialists. In the period between 1917 and 1918 there were numerous personal attacks, especially in Barcelona. The first anarchist groups were quickly dismantled by police forces but during the last year of the WWI the social situation got worse and violence was perpetuated by spontaneous groups of workers.

The Bolshevik three years

After the end of the war there was a deterioration of the economic situation, because of high level of inflation and strong reduction of exports. Economic crisis, which crossed all Europe in the aftermath of the war, produced a lack of essential goods and a lot of job losses. The period between the end of WWI and 1921 is generally known as , because the number of strikes and union struggles reached their apex and levels of social clashes increased in an exponential way. The influence of the October Revolution was very strong in Spain, because it fostered the circulation of socialist and anarchist ideas and encouraged left-wing trade unions to increase levels of union struggle.

This period was inaugurated by the deal between the two main trade unions, CNT and UGT, which during 1918 created , unified industrial local sections of the two syndicates, in order to improve the quality of strike actions. One of the main event of this period was the Canadenca strike in February 1919, which blocked the production of the English-Canadian factory Barcelona Traction, locally known as /, for 44 days and forced the Spanish government to enact the "Decree for the eight-hour working day", limiting the working day to eight hours.

During the year the number of CNT's members increased very fast (from 80,541 in 1918 to 845,805 in 1919) and CNT became the most important trade union in Spain. At the same time repressions which followed the Canadenca strike finally allowed the CNT's extremist wing to take control of syndicate's initiatives. As a result, Seguí's moderate approach was definitely replaced by targeted killing operations and in few weeks several anarchist action groups were born and adopted violence and murders as political tools.