As soon as War had been declared arrangements were put in hand to move the Royal Field Artillery brigades of the 2^nd London Division to Hemel Hempstead. This was to be the second military “invasion” of the town in less than a year, as the area had been the jumping off point for the 4^th Division in major army manœuvres in September, 1913. The big difference was that during the manœuvres the majority of the troops were only in the area for a couple of days, and they were entirely accommodated in tents, so that apart from the extra traffic there was little effect on the civilian population.

By Monday, 10^th August, an advance party of officers were hard at work looking for billets for both men and horses. By the end of the week they had requisitioned many buildings including the Town Hall and the Corn Exchange in the High Street, the Brotherhood Hall, and Boxmoor Hall. Open areas such as Gadebridge Park, the Old Recreation Ground and the adjoining fields of Hand Post Farm were got ready to receive the gunners.

The main bulk of the troops of the 5th and 6th Brigades R.F.A. arrived by train between 4 p.m. and midnight on Sunday, 16th August, and a large crowd of locals turned out to watch them arrive. Their arrival was not without incident. As the troops marched under the railway bridge in Marlowes a dense cloud of smoke belched forth from a cottage chimney, followed by tongues of flame. P.C. Gillett was quickly on the scene and the police held the crowd back as pieces of chimney pot crashed into the roadway. The Fire Brigade, led by Chief Officer W. J. Williams, galloped down Marlowes for the second time in 24 hours and extinguished the fire. Some hours later P.C. Gregory was regulating the traffic in Hand Post Lane when Frederick Hall of Luton decided that he wanted “to assist his country” and started to interfere with the military horses. On being told to go home he became quarrelsome and abusive and was subsequently fined 7s 6d with 6s 6d costs, or imprisonment for 14 days, for being drunk and disorderly.

Many of the townsfolk were startled by bugle calls at about 5.30 the following morning. Within a week the bugle calls in the town were dispensed with (undoubtedly as a result of civilian protests) and, for different reasons, an order was issued to ensure that all public houses closed at 10 p.m. Many local firms found that their carts and wagons were requisitioned for military purposes, and their bright colours were rapidly hidden with a uniform coat of grey paint. On Monday, 19^th August, the Queen’s Westminster Rifles marched into Leverstock Green, while on Wednesday, the 7^th Brigade R.F.A. arrived in Boxmoor, and over the following weekend the 8^th Brigade R.F.A. moved into Apsley. With so many horses and men moving about there were numerous minor accidents, and a room in the Hemel Hempstead Institute was taken over as a military hospital.