Accordingly, while the legal forms of the transfer were being gone through, the young chief made a remark extremely offensive to Paulet, which was resented by a blow in the face with his clenched fist.

Instead of returning the blow, young O'Dogherty hurried away to consult the M'Davitts, whose advice was that the insult he received must be avenged by blood.

The affair having been immediately reported to the lord deputy, who apprehended that mischief would come of it, he sent a peremptory summons to Sir Cahir, requiring him to appear in Dublin, 'to free himself of certain rumours and reports touching disloyal courses into which he had entered, contrary to his allegiance to the king, and threatening the overthrow of many of his majesty's subjects.' His two sureties were also written to, and required to 'bring in his body.' But O'Dogherty utterly disregarded the lord deputy's order.

Taking counsel with Nial Garve O'Donel, he resolved to seize Culmore Fort, Castle Doe, and other strong places; and then march on Derry, and massacre the English settlers in the market square.
Towards the close of April, Sir Cahir invited Captain Harte, governor of Culmore Castle, on the banks of the Foyle, about four miles from Derry, with his wife and infant child, of which he was the godfather, to dine with him at his Castle of Elagh.
The entertainment was sumptuous, and the pleasures of the table protracted to a late hour.

After dinner the host took his guest into a private apartment, and told him that the blow he had received from Paulet demanded a bloody revenge.