As we mentioned, Major-General Morshead (then a brigadier) was at Tobruk when the 6th Australian Division attacked and captured the place from the Italians in late January 1941. After the capture, Morshead was able to inspect the fortress area. When he knew that the 9th Australian Division would have to withdraw into Tobruk after the fall of Mechili and the German pressure, General Morshead was well-prepared with knowledge of the Tobruk area.
After the fall, Lt-Col. Cook was put in charge of the building the base there. Fairly quickly, after the initial area commander was withdrawn to Palestine, Cook became the area commander, as well. Early on, Cook had a newsletter published every day to hand out to the fortress occupants. Colonel Cook had become concerned about the local rumor mill and decided that the thing to do was to publish a newsletter. The newsletter was the work of Sergeant Williams and was called the Tobruk Truth.
From mid-March 1941, Australian brigades arrived at Tobruk. The first was the 26th Btigade and was followed by the 24th Brigade, which only had two battalions. By March 25th, the 26th Brigade left Tobruk to join the 9th Australian Division and the 24th Brigade took over the defense. One feature of the defense was the so-called "bush artillery", captured Italian guns manned by infantrymen who were not trained as artillerymen. They found that most Italian artillery at Tobruk were either damaged or had been exposed to weather so long that they were unusable. The Australians cheated and disobeyed General Neame's orders by bringing large numbers of Italian 47mm anti-tank guns from Bardia. The history says "40mm", but the Italian guns were all 47mm. This is based on the account in Vol.III of the Australian Official History.