This real photo postcard has been in my collection for years and I would appreciate your views concerning the tank and its location, tanslation of the German message, and identification of the unit the sender belonged to. The postmark is dated Sept. 14, 1917
Tank is Mk I or Mk II female, judging by the sponson. I would refine that to say that it is almost certainly a Mk II, as it has a camouflage pattern on the sponson, but the variation on the hull appears more likely to be mud or stains; only Mk I tanks had full pattern camouflage - the Solomon scheme - but some Mk II tanks (painted khaki brown) were fitted with sponsons removed from Mk Is. This gives the distincive appearance of a monotone hull with a camouflaged sponson, which I believe we have here.
That suggests that the tank is one that was lost during the Battle of Arras in April 1917 - the only combat the Mk II was used in, to my knowledge - they were originally intended for training and did not have hardened armour plate, but mild steel which was not bulletproof (the Mk I sponsons of this tank would be the only properly armoured part). As an emergency measure they were put into action, some with armoured Mk I sponsons to help a little, but I think they were hit very heavily by the action.
Someone here on the forum should be able to add much more detail, and I expect there will be someone who can identify the particular vehicle.
The wreck in the photo is tank 586, a MkII female of 11 Co., D Bn., HBMGC (D28). It was commanded by Lt. Clarkson (KIA 11/4/17), and was knocked out south of Riencourt while supporting the 4th Aus. Div. during the 1st Battle of Bullecourt. It is wreck "4" on the map.