During the summer of 1944 all the headlines were about the Normandy invasion and the follow-up campaign to liberate France. With the public's attention in the United States focused on Europe, the campaign in the Marianas was just a secondary story. But just as the invasion of Normandy was significant to victory in Europe, the capture of the Southern Marianas was the beginning of the end of the Japanese empire in the Pacific.

The capture of the Southern Marianas was vital to achieving victory in the Pacific. It would cut the strategic line of communication between Japan and its island outposts in the South Pacific, making supply and communication extremely difficult. The Marianas would also provide the US Navy with forward naval bases, including a very important submarine refueling base. But as important as this was, the ultimate objective of capturing the Marianas was to establish airfields for the B-29 heavy bomber.  From the Marianas the B-29 could conduct the all important strategic bombing campaign that would cripple Japan's ability to wage war. Conducting the bombing campaign of Japan from China was proving to be too difficult to support. The Marianas would be far easier to supply, and the range the bombers need to fly would be greatly reduced.

Therefore, the invasion plans for the Marianas, operational plan Granite II, was completed by December of 1943. It called for the invasion of Saipan, Tinian, and Guam. Saipan was the first target. Saipan was a major headquarters and airbase in the Central Pacific. Because of this it was also the most fortified and heavily defended of the three islands. Tinian's flat terrain would be ideal for building an airfield that could support heavy bombers, bombers that could strike the Japanese homeland. Guam would provide both an airfield for heavy bombers and a forward supply base for future operations in the Pacific.

Guam is the largest of the Marianas, 32 miles long and 10 miles wide. At its narrowest point it is 4 miles across. This isthmus divides the island into two halves that differ greatly in terrain features.  The southern part of the island is dominated by rugged hills, fertile valleys, and scrub forest. The red clay soil quickly turns into thick mud during heavy rains. The northern half is a high limestone plateau, covered by a dense tropical forest. The most suitable amphibious landing areas, with wide beaches and narrow reefs, are located along the central and lower west coast.  

Guam had been a United States possession since 1898, captured from Spain during the Spanish-American War. It was invaded and captured by the Japanese on December 11, 1941. Guam was garrisoned by 271 Navy personnel and 153 Marines. In addition to this there was a 246 man volunteer militia, called the Guam Insular Force Guard. The Japanese landed with a company from the Maizuru SNLF and the 144th infantry regiment. In the brief skirmish the governor surrendered the island. Total US, Guam Insular, and civilian casualties were about 83 and the Japanese lost 7.    

The Japanese Army had about 11,500 soldiers on Guam, the main units being the 29th Infantry Division, the 48th Independent Motorized Brigade, and several tank, artillery and engineer units. The Navy had about 7,000 ground and air unit personnel. The US forces consisted of the III Amphibious Corps, which provided command and control, artillery and logistics support. The major combat units were the 3rd USMC Division (20,388 Marines), the 1st Provisional Marine Brigade (4,500 Marines), and the US Army's 77th Infantry Division (17,958 soldiers).

The invasion plan called for a preparatory aerial bombardment by carrier aircraft and land based planes based bombers. This would be joined by heavy naval bombardment by battleships and cruisers. This pre-invasion bombardment was the heaviest of the war to date. The Orote Peninsula received special attention throughout this bombardment. Nearly all the fixed coastal artillery positions were destroyed before the landing force hit the beaches.

On July 21 the Americans landed on the west coast of Guam. The 3rd Marine Division landed near Agana to the north of the Orote Peninsula, and the 1st Provisional Marine Brigade landed near Agat, which is south of Orote. Lacking amphibious landing craft the 77th Infantry Division had more difficulties landing. The landing craft could not get over the reef, so the soldiers had to wade ashore from the edge of the reef.

The Japanese counter-attacked during the first few days of the invasion, mostly at night. The attacks were intense and the fighting was close in. Service units and hospitals had to defend themselves as the Japanese penetrated into the rear areas. This intensity did not let up until the Japanese Army attackers were nearly wiped out, leaving just scattered remnants. By the 25th the Orote Peninsula was cut off. Orote was declared clear on the 29 July. Over 2,500 Japanese were killed defending Orote, and more than 250 pillboxes and fighting positions were cleared. The Marines suffered 874 casualties.

The Japanese counterattacks against the American beachheads had exhausted the Japanese. By August they were running out of food and ammunition. The Japanese had lost half of their trained combat troops. Most of their tanks were already destroyed. The battered and exhausted Japanese withdrew from the south of Guam, planning to make a stand in northern part of the island. Strongpoints were planned around Mt Barrigada and Finegayen village, a second one near Ipapao Village, and a last stand position at Mt Santa Rosa. But with resupply and reinforcement impossible due to American control of the sea and air around Guam, the best the Japanese could do was to delay the inevitable and inflict as many American casualties as possible.

Heavy rain, thick mud, and dense jungle made conditions difficult for the Americans as they advanced to the north. Heavy resistance was met around Mt Barrigada and Finegayen.  Once these areas were cleared the Japanese gradually fell back to Mt Santa Rosa. The Americans estimated there were around 3,000 Japanese left, but when Mt Santa Rosa was cleared only 500 dead Japanese were found. Organized resistance had ended. The rest had scattered into the Jungle. When Guam was declared secure on 10 August an estimated 7,500 Japanese were still scattered across the island.


Guam Playtest Map - Click to Enlarge

The Game  

Guam is a large island for a Pacific island battle. However, it has the fewest exclusive rules of the three games currently in the series (Saipan & Tinian and Attu & Kiska). This means that it should be the easiest and quickest to learn. The large size of the island allows both players to employ a wide variety of strategy options. As with most of the other games in the series, the victory conditions do not focus on geographic locations. The situation is simply a fight between both sides.

Planning is the first step, and quite possibly the most important one too. The US player has to examine the Japanese dispositions, by looking over the map and using the limited intelligence rules to try to figure out where the Japanese main defenses are. Next in the planning cycle is to pick landing locations and then select the composition and order of your beachheads and landing forces. Once the US player lands on the island he has to eliminate the Japanese units. That is a pretty simple goal, but it may not be as easy as it sounds! You have to do it within the game’s time limit. He will have to find that perfect balance between time, maneuver, and combat. Too slow, cautious, or methodical and you run out of time. Too impatient and aggressive and you will suffer too many casualty points to win.

In Guam the Japanese player has many options; the most of all the games in the series. You still have many of the same conditions as the other games, such as fortifications, being outnumbered, defending against an overwhelming invasion, and your opponent has air and naval superiority. However, you have a large enough force on a large enough island to allow far more opportunity for maneuvering. The Japanese player also has a variety of terrain types to incorporate into his defense. The clever use of dummy positions can fool the US player, making him attack unmanned positions or chasing scattered dummy units all over the map. But as in all the games, the Japanese player must have a well thought out plan with several courses of action in mind. Fortifications and dummies must be well placed in anticipation of US player moves.


The Island War Series

Unit size: Platoon, Company, and Battalion.
Scale: Hex scale: 1/2 mile.
Game Turn: Each turn represents 12 hours.

The Island War Series game system is a simulation of ground combat in the Pacific during World War II. Each game in the system represents a battle between Allied and Imperial Japanese forces on one of the many Pacific Islands. The series includes Saipan/Tinian -Vol. I,  Guam - Vol. II and Attu & Kiska - Vol. III.

Two sets of rules are provided with each game. The first contains the Standard Rules that are common to all the games in the Pacific Island Series. The second set contains the Exclusive Rules for each game in the system, which includes Special rules, the Initial Deployment and the Reinforcement Schedule. Generally the unit scale is battalion, but there are company and platoon formations represented. The time scale, unless noted in the Exclusive rules, is 1/2 day per turn.

The focus of the series is on the land battles of the Pacific, therefore all naval and air forces are abstract. The games are designed for two players, but can accommodate multiple players. For example, one player can play the US Marines, one can play the US Army, and the third plays the Japanese.

This series of games is loosely based on or inspired by several different game systems, including SPI's Island War series and GRD/GDW's Europa series, but many concepts are quite original. The tactical situation for the defender can be described as "against the odds", which means it will be very difficult for the player playing the defender to win the game tactically. The victory conditions are designed in such a way that the defender can win by performing better than his historical counterpart. This also puts a lot of pressure on the attacker because he cannot afford to make many mistakes.

Game features include:

  • Limited Intelligence
  • Amphibious Landings
  • Weather and Night Rules
  • Banzai Attacks
  • Coastal Defense Units
  • Beachheads and Replacements
  • Fortifications