Okay, gentlemen, the stories about the Flanders and Gallipoli and it's endless trench clashes are famous, but I'm yet to see a good illustration on Eastern Front and etc.
How was the mobile warfare in Russia, Caucasus, Middle East, Balkans etc? Napoleonic tactics were far outdated, and technology was not advanced enough to have armored divisions, advanced aircraft, and generally mechanized and motorided units like in WW2 and beyond.
So how did a battle went like? Just thousands of men found each other in forest/desert and shoot randomly? How did generals plan maneuvers and how did soldiers maintain communications with the upper command? How did generals know what kind of enemy was waiting for them?(No aerial reconnaissance like WW2, and they don't come in open formations like Napoleonic Wars)
If you look at Field Marshal Viscount Allenby's Palestine campaign with the Egyptian Expeditionary Force (EEF), you can see the beginnings of the mobile warfare tactics of WWII. In place of tanks and armored cars, Allenby had the Desert Mounted Corps. The DMC had a mix of cavalry, mounted infantry, and artillery, and could act as a fast-moving combined-arms exploitation force. At Beersheba, there was a deception campaign to fool the Turks into believing the Commonwealth forces were still arranged against Gaza, while some of the infantry and the DMC slipped east to attack Beersheba. This was helped by the German and Turkish belief that Beersheba was too far from water sources for a large force to attack. Allenby then used the DMC to maneuver around the Turkish left flank where the defenses were weaker. Allenby's plan made good use of artillery and machine guns to suppress Turkish defenses. The Australian and New Zealand Lighthorse mostly attacked dismounted with success, but the final 'cavalry' charge was made by mounted Lighthorsemen, to the surprise of the Turks and their German advisers (they anticipated the Lighthorse would dismount to attack). (The depiction of the charge in the movie The Lighthorsemen is magnificent, if not 100% historically accurate.) Exploitation of the collapse of the Turkish left flank by the Anzac Mounted Division forced the Turks to abandon their positions at Gaza.
Allenby also made good use of his aircraft for reconnaissance, to interdict Turkish supply lines and to harass retreating units. His integration of aircraft, mobile combined-arms force, and aggressive exploitation were, for the time, revolutionary. You asked about communications, and this was a problem throughout the campaign. Wired comm systems only worked well when the line was unmoving, and the range of visual (semaphore, etc) was limited and generally exposed the signalman to enemy fire. Allenby moved his headquarters close to the front line from Cairo, where his predecessor had kept his staff. Likewise, his subordinate commanders, particularly Sir Henry George Chauvel, commander of the Desert Mounted Corps, kept their HQs more forward. Chauvel established a 'fighting HQ' (effectively a TAC in modern US parlance) so he could stay up with the mobile forces. The commanders then used a combination of dispatch riders, wired communication and messages dropped from aircraft.
Preston, R. M. P. The Desert Mounted Corps: An Account of the Cavalry Operations in Palestine and Syria 1917–1918.
Bruce, Anthony. The Last Crusade: The Palestine Campaign in the First World War.
Nuño, Geronimo . Incomplete Victory: General Allenby And Mission Command In Palestine, 1917-1918
/u/RonPossible gives good idea of what manoeuvre warfare was like in the Middle East; I've given answers as well on pre-trenxh warfare fighting in the west, and strategy and tactics in the Eastern Front if you're interested.
I can also say that there was in fact aerial reconnaissance in WWI; in manoeuvre warfare it was important at Tannenberg, the Marne and the Serbian Campaign of 1915. Fighting had also come a long way since Napoleon, with units advancing in loose order, typically with machine gun and direct/indirect artillery support, as had been previewed in the Russo-Japanese War. By 1916, the Germans and Russians at least had begun forming shock units trained in infiltration tactics, and the Gorlitz-Tarnow and Brusilov Offensives are testimony to how sophisticated artillery methods could be.
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