POLVERI, CONGIURA delle. — Conspiracy to blow up, on 5 November 1605, the English Parliament and, together with its members, King James I. The motive was the long and intolerable harassment and persecution suffered by Catholics from Henry VIII onward, which had resumed under James I, contrary to the promise he had made upon ascending the throne to put an end to them.
Various English nobles took part under the leadership of Roberto Catesby, initially in conjunction with Giovanni Wright and Roberto Winter, who were later joined by Guy Fawkes, Tommaso Winter, Francesco Tresham, Tommaso Percy, Everardo Digby, Ambrogio Rookword, Roberto Keyes and Giovanni Grant. On 11 December 1604, after first renting a house near the Palace of Westminster, they began to construct a passage toward a main wall of Parliament, piercing halfway through it; then, interrupting this work in order to make use of a cellar directly beneath a room of the Palace, they brought into it 36 barrels of gunpowder, concealing them beneath a pile of wood and coal. Once the work was completed, the conspirators dispersed while awaiting the opening of Parliament, which was postponed until 5 November 1605.
On 28 October, Lord Monteagle was warned by one of the conspirators, certainly Tresham, his relative, not to go to Parliament on 5 November in order to avoid serious danger. Tresham probably intended thereby to avoid condemnation for himself and to give the conspirators time to save themselves by fleeing. The government, having been informed, took no action, nor did it order a search until 4 November. During the night of the 5th, Fawkes was arrested near the cellar with the fuse in his pocket; his accomplices had time to flee to Holbeche, where, however, they were pursued; on 8 November Catesby, Percy and Wright fell dead in the field; the others, captured, taken to London and tried, were executed, some on 30 and some on 31 January 1606.
The first official news of the discovery of the conspiracy was not issued until 7 November, in a report by Robert Cecil which, revised and expanded, reappeared two days later under the title: A True and Perfect Relation of Whole Proceedings against the late and Barbarous Traitors. This, with the addition of the king’s speech to Parliament, certain testimonies by the conspirators and some further alterations, appeared in a 3rd edition the following March under the title King's Book. The government’s “true and perfect relation,” however, contains glaring contradictions and falsehoods and, in the judgment even of learned Protestants entirely above suspicion (cf. Enc. Britannica, XII, 11th ed., 1910, p. 729), is full of improbabilities (e.g., the transport of the material resulting from the excavation and of the 36 barrels of gunpowder without anyone noticing; the absence of any trace of the

But the account presented by the government stopped at nothing in order to achieve its aim of oppressing the Catholics and suppressing the Roman Church; consequently, the persecution became more violent and the legislation more draconian, thereby increasing the number of martyrs.
In conclusion, it must be held that the essential features of the “true account” are certain (cf. O. Pfüll, Die Controverse über die Pulververschwörung, in Stimmen aus Maria Laach, 56 [1869], pp. 41–57, 142–57, 286–99), and that consequently the intention on the part of certain Catholics to blow up Parliament did exist, and that an attempt was also made to carry it out; how far, however, the conspirators proceeded in their undertaking will perhaps remain a mystery forever.
J. Spillmann, Die Blutzeugen unter Jacob I, ..., Freiburg im Br. 1905, pp. 18–81; J. Brodrich, The Life and Work of Blessed R. card. Bellarmino, II, London 1928, pp. 144–86.