Why did Conrad feel the need to attack both Serbia and Russia at once? Doesn't it make more sense to smash up one enemy before trying to smash the other?
Conrad had two plans, one for war with Serbia alone, and one for Russia and Serbia. Plan A had three armies attacking Serbia, and two guarding the Russian border. Plan B had only two armies attacking Serbia, and three attacking Russia.
He implemented Plan A to begin with, then changed his mind and implemented Plan B. As a result one Austrian army (the 2nd, I think) spent the critical first few weeks transiting from the Serbian to the Russian front.
Why not stick with Plan A, stay on the defensive against Russia, and defeat the Serbians quickly, freeing up two armies to reinforce the Russian front in a couple of months?
A-H Grand Strategy for WWI
Actually Austria-Hungary's plans for war were called Plans B and R.
Plan B (for Balkans)- With this plan, six Austro-Hungarian armies would be fielded, three to invade Serbia, three to guard Austria-Hungary's border with Russia.
Plan R (for Russia)- This allowed for a greater volume of troops to guard against Russia, whilst assuming German activity in the north. Four armies were to be deployed against Russia and two against Serbia. The problem with this was that in commiting to the Schlieffen Plan Germany the bulk of its manpower to the west before turning its attention to the east. This was the chosen plan in August 1914.
The answer to your question is (I believe) that Austria-Hungary felt it could defeat Serbia with those two armies and that Russia would pose a greater threat, therefore justifying Plan R.
Plan B (for Balkans)- With this plan, six Austro-Hungarian armies would be fielded, three to invade Serbia, three to guard Austria-Hungary's border with Russia.
Plan R (for Russia)- This allowed for a greater volume of troops to guard against Russia, whilst assuming German activity in the north. Four armies were to be deployed against Russia and two against Serbia. The problem with this was that in commiting to the Schlieffen Plan Germany the bulk of its manpower to the west before turning its attention to the east. This was the chosen plan in August 1914.
The answer to your question is (I believe) that Austria-Hungary felt it could defeat Serbia with those two armies and that Russia would pose a greater threat, therefore justifying Plan R.
The a-h Army had Group A to fight the Russian in Galicia, Group Balkan to fight Serbia, and Group B to reinforce one of the two depending on the situation.
Conrad von Hötzendorf and his staff (the Germans also) thought that it would take the Russians longer to mobilize. They didn´t recognize that the Russians already had 2/5 of their peace-time forces concentrated in Poland (Keegan).
When this became clear, they still let group B proceed to Serbia (it was already on the way) to participate in the attack, and it would be sent to the russian front soon afterwards. While it is true that the redirecting of Group B would have been difficult due to the fixed train plans, there was certainly a fair share of hate against Serbia involved. Which means it was rather an emotional than an intellectual decision.
Conrad von Hötzendorf and his staff (the Germans also) thought that it would take the Russians longer to mobilize. They didn´t recognize that the Russians already had 2/5 of their peace-time forces concentrated in Poland (Keegan).
When this became clear, they still let group B proceed to Serbia (it was already on the way) to participate in the attack, and it would be sent to the russian front soon afterwards. While it is true that the redirecting of Group B would have been difficult due to the fixed train plans, there was certainly a fair share of hate against Serbia involved. Which means it was rather an emotional than an intellectual decision.