Memorandum by Joseph P. Walshe on the response of British troops in
Northern Ireland to a German invasion of Ireland

If Germany invaded Ireland what steps would the British troops in the Six Counties be likely to take?

1) Their Air Force would attack the Germans. Consequently, they would take aerodromes in the neighbourhood of Dublin, establish depots there, as well as service units. It is very likely that the men and materials for this purpose are now in Newry ready for immediate transfer to the Dublin area.

2) No doubt the British are most afraid of a German invasion through Donegal, and they must have made preparations to advance immediately to Lough Swilly from Derry. Donegal would be overrun at once by the British troops now stationed in Derry. Our troops in Donegal would, in those circumstances, be faced with the immediate problem of the attitude to be taken towards the British troops.

3) If the Germans invaded us first, and we had to request the aid of the British, we should have to inform them before they actually crossed into our territory of our plans for the demolition of bridges, etc. This would be done through Liaison Officers who would also be responsible in such circumstances for the requisitioning of billets for the invited troops. The Liaison Officers would also inform the invited troops of the medical arrangements, hospitalisation of wounded men, etc.

4) Supplies for the invited troops would come to Dublin by rail, whereas the troops themselves would come by road. The Liaison Officers would have to know all about rolling-stock facilities. We should have to allow the invited troops to make a general base in or near Dublin for all kinds of supplies of clothing, munitions, etc. Dublin, being a port, provides the obvious site for such a supply base.