One hundred years ago today, on May 12, 1916, James Connolly became the last of the Easter Rising leaders to be put to death. So weakened was he from injuries incurred during the fighting, he had to be bound to a chair to face his executioners in the Stonebreakers’ Yard at Kilmainham Jail in Dublin.

Asked if he’d pray for the members of the British Army firing squad, he declared that he would pray for all brave men who do their duty.

Connolly was the only socialist among the Rising’s leaders, and he stands as the most important Marxist revolutionary from Ireland.

He founded the Irish Socialist Republican Party (ISRP) in 1896; created Ireland’s first Marxist newspaper, the Workers’ Republic; collaborated on the Irish Citizen Army (a militia set up to defend workers during the great Dublin Lockout in 1913); ran the Irish Transport and General Workers’ Union (ITGWU) with James Larkin; and finally led the 1916 insurrection. The range of Connolly’s concerns and radicalism is astonishing.

Connolly bluntly declared that one of the ISRP’s purposes was “the incidental destruction of the British Empire.” Marx before him and Lenin after him likewise believed that an attack on the empire from even a peripheral location like Ireland could have a devastating effect.

Though he died during a republican uprising in Ireland, the struggle against capitalism was always at the heart of his ideas and actions. More than most of his colleagues, he was an internationalist. He recognized the shared struggle in Scotland and in Ireland, in earlier Irish history, in ongoing struggles across Europe and the colonized world, and also in the United States.

In 1902, when the ISRP and the American Socialist Labor Party (SLP) had already started to work together, Connolly embarked on a lecture tour of the United States. In February of that year, the SLP republished his pamphlet Erin’s Hope: The End and the Means. The SLP’s newspaper, the Weekly People, ran Connolly’s articles from the Workers’ Republic, hoping to find an audience among Irish Americans.

The ISRP and SLP hoped his tour would advance the purposes of both parties. His first talk — which took place immediately on his arrival in the United States — was at the Cooper Union in Manhattan on September 15. The New York Times called him “an Irish socialist agitator.” The SLP motion that welcomed him said that

his mission wishes to destroy the influence of the Irish Home Rulers and the bourgeoisie in Ireland, and their allies who trade on the Irish vote in this country to the economic detriment of the Irish working men in this country. . .

Connolly toured all over the East Coast and into the Midwest on a relentless schedule in the fall of 1903. Repeatedly, he tried to tear Irish-American workers away from mainstream US parties by pointing out the parties’ class bias.

The bourgeois politics of Republicans and Democrats in the US, he argued, corresponded to the constitutional bourgeois-nationalism of Irish Home Rulers, which had repeatedly betrayed the interests of the Irish poor.

All the while, Connolly was sending the income from his lectures to the ISRP back in Dublin.

The tour concluded with joint talks by Connolly and Daniel De Leon, leader of the SLP. The event was successful, and relations between De Leon and Connolly amiable enough. But the two leaders disagreed about where to locate the leading edge of socialist struggle.

Connolly was clear that the SLP was the future of American socialism and he greatly relished the party’s disavowal of the the Second International’s reformism. But he also noted the corrosive influence of American individualism and lawlessness, even in the union movement, and argued that the United States was hardly a leader in the development of socialism.

De Leon replied that American socialism was in fact ahead of its European allies and that America would prove to be the center of the struggle between capital and labor. Their debate started a running battle that would dog Connolly’s entire relationship with American socialism.

Connolly’s return to Dublin was not a happy one. He discovered that the funds he had sent his ISRP colleagues had not been used to keep up publication of the Workers’ Republic as intended and that the party was fracturing. In spite of newfound political work with Scottish socialists, Connolly was — not for the first time — struggling to feed his family. Permanent emigration to the US seemed like the best option.

When he arrived back in the United States late in 1903, he found De Leon cool and unhelpful. Because he was not a card-carrying AFL member, he could not get work with the Weekly People, as he had hoped. Work as an insurance collector kept his head above water, however.

In early 1904, De Leon and Connolly had a prolonged public quarrel in the pages of the paper over wage-increase campaigns. De Leon argued that wage increases would always be offset by price increases. Connolly saw that this position would drain workers’ campaigning energy and he fought back aggressively.

He also criticized what he saw as the generally anti-religious aspects of the SLP posture. Certainly, reflex atheism was not going to win much support for the SLP among Irish-American workers. But arguing with De Leon put Connolly at variance with the SLP’s rigid Second International view of history, which saw the collapse of capitalism as inevitable.

Where the SLP and the International envisaged capitalism’s demise as entailed by “scientific” laws of history and, hence, fore-ordained, Connolly feared that this attitude would lead to passivity and an unwillingness in supposedly revolutionary socialist parties to support proletarian workplace struggles. For Connolly, who saw the traces of the class war in even the smallest conflict with employers, this was anathema.

Yet it’s notable that, while he was in the US, Connolly wrote his most important book, Labour in Irish History, which, anticipating Lenin by some years, tackles the issue of socialist development in a backward agrarian society head-on.

Connolly eventually brought his family to the United States and settled in New Jersey. Agitating in his free time, he continued to work and speak for the SLP in spite of the tension with De Leon.

The birth of the Industrial Workers of the World (IWW) in 1905 gave Connolly a new organizational and ideological focus. He quickly became involved. As early as 1898, he’d revealed his proto-syndicalist views when he advocated for the revolutionary function of socialist trade unions: “the trade unionist wishes to limit the power of the master but wishes still to have ‘masters,’ the socialist wishes to have done with masters.”

After George Stennenberg’s death in 1906, Connolly joined the Haywood-Moyer defense committee of Newark and became a significant campaigner for the Wobblies on the East Coast. The IWW was impatient with the established US labor organizations because of their craft orientation, their occasional ethnic exclusivity (which sometimes dismissed Irish workers as inherently reactionary), and their neglect of the most impoverished or marginalized workers. The Wobblies were also openly critical of the AFL’s corruption.

Under pressure from the IWW, the SLP was becoming more sympathetic to union activism — a transition Connolly supported. Eventually, the tension between Connolly’s Leninist support of vanguardist parties — the ISRP in Ireland, the SLP (though it advocated industrial unionism) in America — and his Wobbly syndicalism became too great to bear.

Connolly remained a member of the SLP until 1908, but he continued to clash with De Leon at party conventions. In 1907, he became a Wobbly organizer, which allowed him finally to break with De Leon and the SLP. In 1908, he founded the Irish Socialist Federation, an organization designed to appeal to and to recruit Irish-American workers, and started publishing and editing their newspaper, the Harp.

All the time he was in the United States, Connolly strove to keep in touch with Irish comrades and to stay abreast of developments back home. News of the creation of an Irish syndicalist union, the Irish Transport and General Workers’ Union, in 1909 encouraged him to return to Ireland in 1910.

His American experience was crucial to his ideological and revolutionary development. When he left Ireland, he was the leader of a tiny socialist party that bravely but mostly unsuccessfully contested local elections; he returned with a new organizational and strategic vision based on the mass mobilization of workers — “One Big Union” — and the general strike as a political and revolutionary weapon.

This both strengthened and weakened him. On the one hand, the IWW’s lessons on the importance of mass mobilization and the strike were essential. Syndicalism taught him about the power-in-depth that could be exerted in the realm of civil society. This would rapidly lead to the tremendous struggle of the Dublin Lockout in 1913, when the city’s employers sought to break the ITGWU.

But Connolly’s syndicalist confidence that the revolutionary frontline was largely located in the workplace led him to somewhat sideline the idea of the revolutionary party as such, to argue for the necessity of working with a broad range of socialist, labor, and reformist opinion, and to think that revolutionary activity and even insurrection could succeed without grasping and defeating the machinery of the state.

This left him vulnerable when the ITGWU lost the lockout and when Irish workers responded in overwhelming numbers to John Redmond’s call to serve in the British Army in 1914. It fundamentally shaped his relationship with Irish republican revolutionaries during the rising.

His death deprived the Irish left of its greatest and most fertile leader. The tumultuous labor struggles from 1917 to 1923, when Irish workers declared over one hundred soviets and used the general strike powerfully as a political weapon, suffered from his absence.

Most of all, Connolly’s internationalism and anti-imperialism linked his brand of Irish socialism with the most progressive struggles across the globe and gave it a critical edge at home. His prediction that both physical-force republicans and bourgeois constitutionalists would invoke the power of the masses and then abandon them was fully borne out in the emergent Free State after 1922. The Irish left needs Connolly’s relentless and uncompromising focus more now than ever.