James was born in Belfast, but was a medical student in Cambridge when WW1 broke out. He immediately joined up. After training, he became a 2nd Lieutenant and was sent to France with the Royal Fusiliers, but although severely wounded twice, once in the Battle of Loos and again in the battle of the Somme he survived the war. He was demobilised in 1920 while serving in Egypt.
Rather than returning to Cambridge to finish his studies, he joined the newly formed Palestine Police in what was still officially Enemy Occupied Territory, with the rank of British Reserve Inspector, the term used for deputy assistant superintendents in those days.
The first two years of his service were spent in hedonistic Jerusalem, enjoyung the company of the fishing-fleet, debutantes who toured the middle–east and India with mothers in search of eligible sons-in-law, commodities in short supply in England after the carnage of WW1. Despite this, he was immensely popular with his male colleagues.
In 1922 he was posted far from sophisticated Jerusalem into the real Palestine as police district commander of upper Galilee, where bandits roamed the wild hills and most of his time was spent patrolling the countryside on horseback in charge of a team of Arab and Jewish police.
On April 15th 1922 James was leading a patrol consisting of himself, Inspector Ibrahim Effendi Oweida and six Arab Constables all on horseback about ten kilometres south of Lake Galilee. Down there in the Rift Valley so far below sea- level, the temperature, touching on 100 F, was almost unbearable. The surrounding countryside was barren wilderness, apart from a jungle of reeds and low trees lining both sides of the River Jordan which, from the sound of it was in full spring flood. James realised his horse needed water, but he had to wait until he found a path trampled through the reeds before he could ride his horse down to the river.
One of his men warned him that the Jordan at this time of the year was treacherous, but Inspector Oweida contradicted the constable and rode his horse into the water where he allowed it to stand still to drink.
James followed him but Oweida’s horse began to struggle as it sank into the soft mud of the river bed. The inspector, who was unable to swim, was thrown into the water and carried away.
James immediately jumped off his own horse into the swirling water and succeeded in getting hold of Inspector Oweida, but handicapped by the man's weight, found himself unable to beat the strong current. Both men were carried away, never to be seen alive again.
When Jame’s body was recovered, he was buried in Jerusalem, his grey British granite headstone the first of the many to appear among the white stones in cemetery on Mt. Zion during the following years .
Some good, however, came out of his sacrifice. Arab policemen were now respectful of the handful of British police, and the Force had no more difficulties in recruiting local Arabs. It was said among them, “These Inglizi will sacrifice their lives for us.”
The plaque in the cathedral reads:
“To the glory of God and in memory of Capt. James Wesley Mackenzie of the Palestine Police (late Royal Fus,) who met his death in a gallant attempt to save the life of a brother officer, Inspector Effendi Oweida, in the river Jordan nr Jisr Mejamieh on 15th April 1922. Erected by his officers and friends"
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