According to the agreement reached by the two imperial marshals in the city of Klaipeda at the mouth of the Neman River, in late July, Marshal Macdonald's 10th Legion (Prussian Legion) set out again from Galghidai, following the winding road between dense forests and large swamps, heading northeastward, Riga Fortress 168 kilometers away, passing through Tercyai, Siolia, Yergava and other places along the way.

The combat objectives of the 10th Legion composed of the Prussians were very obvious. In September, the Riga Fortress was completely occupied, and an outpost position was captured in attacking St. Petersburg, and the main forces on the right wing of the southern front: the 2nd Legion (Marris Udino) and the 6th Legion (Marris Saint Sier) were surrounded by the Russian capital - St. Petersburg along the Baltic Sea.

At the same time, in addition to ensuring the safety of sea supply on the Danze-Konisberg-Klaipeda line, a squadron will also head north along the Baltic Sea, break through the Ilbe Strait, invade the Gulf of Riga, and assist the 10th Legion to capture the Riga Fortress guarded by 18,000 Russian ** Army.

In addition, the ground troops commanded by Desai (Second Army, Third Army and Guard Division) not only serve as the general reserve of the 10th Corps, but also ensure the safety of the supply lines from the Neman River to the Riga front line, and send troops to clear out armed rebels hidden in the countryside, jungle, lake wave, swamp, and rivers. This is also the combat method that Desai is very good at. After successfully conquering a series of wars between Gruna, Catalonia and Portugal, Desai was known as the commander of the French marshal who is good at appeasement.

In addition, given the advanced and complete equipment of the field hospitals assigned to the Desai Legion, the large number of military doctors and superb skills, Marshal Macdonald, who was envious, simply handed over the field hospital of the 10th Legion to the general military medical officer Earl Kava for management.

In terms of division of labor arrangements between the two legions, Desai suffered a lot on the surface. He not only had to act as the local maintenance president, but also was responsible for the security of supply and logistics, dispatched naval fleets to assist friendly forces on the ground, and also had to bear the medical care of the wounded soldiers on the front line. In addition, McDonald's battlefield intelligence source also needed strong support from the agents of the Military Intelligence Bureau.

For the 10th Legion, with a superior force of 32,000 (elite Prussian army), a large-scale besiege of 18,000 Riga defenders composed of the Miscellaneous Army and Russian militia. The ** army led by General Essian is naturally no problem to win. Of course, Marshal Macdonald also needs intelligence and supply support, as well as strong cooperation from the Baltic Fleet.

As compensation for the Baltic Legion, MacDonald made a commitment to Desay: any spoils of the 10th Legion will be handed over to friendly forces for free, and agreed to trade between Poland and Catalan merchants in the French-controlled areas, and allowed the military liaison officers sent by Desay to enter Konisburg to coordinate the allocation of weapons, ammunition and military supplies between the two legions.

Desai readily accepted these arrangements. It should be noted that the Polish king was not interested in the spoils of the 10th Legion or the trade rights of the occupied areas, but the Polish army could legally enter Konisburg and prepare in advance for the annexation of East Prussia. This obviously violated Napoleon's previous instructions, but MacDonald, who was on the front line of the battle, would not have taken care of so much. Without Desai's full cooperation, even if his 10th Legion successfully came to Riga, he would have become powerless to fight again due to various combat losses.

Long before the 10th Legion crossed the Neman River, General Barbanegel's second army had swept away the townships of Palanga, Prunge, Gargeride and other towns, and forced the weak Russian troops to abandon the three important cities of Tersia, Sioria and Paneves. Therefore, on July 29, when Marshal Macdonald led his troops to the Riga Fortress, the road was unobstructed.

On August 2, the 10th Legion had arrived at the city of Yergava, which was less than 30 kilometers away from Riga. With the cooperation of more than 2,000 militias, the Russian regular army, with only one regiment, established a not-solid defensive position in the southern suburbs of Yergava, and carried out extremely heroic resistance, successfully blocking Macdonald's Prussian Legion for 15 hours.

The troops that carried out the southern suburbs of Yergava's highland blocking war were affiliated with the most elite Lithuanian Guards in Russia. The main commander was Colonel Udom, the commander of the infantry regiment; and his deputy, Lieutenant Colonel Timofeyer.

After learning about the deployment information of the Russian army from Desay, Lieutenant Colonel Koror, McDonald disagreedly ordered a Prussian light cavalry to break through the defense line of the southern suburbs of Yergavan and encircle and annihilate the Russians stationed there, but suffered a crushing defeat.

When facing the rapid attack of the "French cavalry" (the Russian official documents have regarded all the European coalition under Napoleon as the French), Colonel Udom has long arranged his troops in the highlands to fight against the attacks of the Prussian cavalry.

Despite facing a large number of enemies, the Russian soldiers who were holding the high ground showed great courage and confidence. They did not start volleys until the Prussian cavalry were close enough, and shouted "Ula", disrupting the formation of the Prussian cavalry and successfully drove the enemy off the high ground, causing huge casualties. Two consecutive times, the Russians repelled the attacks of the Prussian cavalry with this shortcut.

In the evening, Marshal Macdonald, who was insulted by the defeat of the offense, sent elite breastplate cavalry to join the highland battlefield. At this time, Lieutenant Colonel Timofeyer had replaced Colonel Udom, who was seriously injured, as the commander of the Yergava defense line.

Lieutenant Colonel Timofeyer, who was on the front line, ordered the soldiers in the square formation: "Prepare, no one is allowed to open fire without my order!" The Russian commander told his soldiers at the first time, "The French livestock will not attack the walls made of cold bayonets, so if the breastplate cavalry rushed to you, I will order the horse's face with a bayonet!"

Before the sun set, the 10th Legion's breastplate cavalry surrounded the Russian infantry phalanx from all directions. The mighty and majestic Prussian cavalry spread out like waves. At this time, the Russian infantry phalanx was like a small island swaying in the huge steel waves formed by breastplate cavalry. However, the attacking troops were unable to disintegrate the Russian army and break through the positions they held.

After the first charge, the Prussian breastplate cavalry quickly re-arranged 30 steps away from the Russian infantry phalanx, preparing to assemble again to attack. In order to prevent this situation, Lieutenant Colonel Timofeyer used each rider to find the gap in his position, shouted "Ula", and personally led the Russian soldiers to wait for an opportunity to fight back.

The Russian infantry picked up the bayonet and attacked. The cavalry in front of them was attacked by the bayonet before they realized what had happened. After suffering major casualties, the morale of the attacking party was severely frustrated and it was difficult to maintain the formation. They had to retreat.

Before dark, the Prussian breastplate cavalry launched another attack with the cooperation of the light cavalry. However, the same pattern continued and was soon defeated by the Russians. When the attacking Prussian cavalry was forced to retreat, some comrades were still trapped in high ground positions, and most of them became prisoners of war for Russian infantry. After being disarmed, these prisoners were escorted to the Riga Fortress 30 kilometers away.

Late at night, with the help of the cover of night, Lieutenant Colonel Dimofey, led the remnant Russian troops to voluntarily abandon the high ground and evacuated northward from the city of Riga. When entering the city, the snare drums and the horns were ringing, and the Lithuanian Guards were warmly welcomed by commander Essian. They successfully fought against the breastplate cavalry with bayonets, and defeated the "Iron Man" countless times with lead bullets, which severely destroyed the enemy's spirit.

In this service, the Russians suffered more than 1,200 soldiers (mostly militias), but they won a local battle and successfully boosted the morale of the fortress defenders; at the same time, the Prussian Legion lost 800 people (including breastplate cavalry and light cavalry). It was not until dawn the next day that the 10th Legion entered an empty city that had been abandoned in a mess.

Lieutenant Colonel Koror, who witnessed the entire offensive and defensive battle in the southern suburbs, later wrote to Desai, gave high praise to the hard-working and tenacious fighting spirit of the Russian soldiers, as well as the military qualities of the two battlefield commanders, saying that "Russian soldiers are monsters forged with special materials such as steel, and are not afraid of the enemy or death!"

As for the performance of the Prussians in this battle, Lieutenant Colonel Koror still won the weak and failed to regain his former self-confidence after the past five years. The Prussians "although brave, they lack tenacity; despite obedience, they lack the sense of cooperation. The commanders of the Prussian army are rigid and conservative, have no ability to respond to the battlefield, and are often in a bad situation of passive beating... In the short term, the combat capabilities of the Prussian army cannot pose an effective threat to Poland."

On August 4, after a brief rest, the main force of the 10th Legion left Yergava, continued to advance northward, and arrived at the city of Riga the next day. In addition to the garrison of the troops along the route and the casualties caused by the battle, Marshal Macdonald's Prussian army was less than 30,000, but compared with the 17,000 Russian troops in the city of Riga, the attacking side still had an absolute advantage in terms of force. Among the garrisons in the Riga fortress, most of the Russian militia soldiers were recruited shortly, while there were only 4 elite infantry regiments like the Lithuanian Guards. After the Yergava blocking war, the number was less than 3,000.

On the afternoon of August 6, the 10th Legion completed the siege of the Riga Fortress. At the same time, the Riga Squadron, a Baltic Fleet composed of 4 battleships and 12 patrol ships, also led to the intersection of the Ilbe Strait and the Baltic Sea on August 7, preparing to enter the Gulf of Riga and participate in the sequence of siege of the Riga Fortress.

At dawn, Colonel Mayar sent two regiments of marines, and under the cover of heavy artillery artillery, they captured the Russian army's coastal defense bases at both ends of the Irbet Strait: Sare Fortress and Korka Fortress.

After evening, the Riga squadron, who was informed, was on high alert in the waters of the Korka Fortress and attacked the Russian naval fleet that was trying to sneak attack on its own. After sinking two ships and capturing one Russian warship, the Baltic squadron drove all the remaining Russian navy back to the anchorage of Riga Port to take refuge, and then cut off the maritime access between Riga and St. Petersburg.

In the early morning of August 9, the Baltic Riga squadron commanded by Colonel Mayar sailed into the waters near the Riga Fortress. On this day, under the heavy siege of the naval fleet and the 10th Legion, the land and sea areas of Riga were effectively controlled by the French army. The defenders lost contact with St. Petersburg, and the entire Riga city had completely become an isolated city.

At noon on August 10, Marshal MacDonald sent his adjutant to enter the city of Riga with a white flag. He asked the defenders to surrender to him immediately, but was rejected by the fortress commander, General Essian.

Two hours later, the fortress offensive and defensive battle broke out as scheduled.
Chapter completed!