HIS greatest adversary labelled him "King Hob" - the royal yokel - and many academics have questioned his intellectual prowess.
But Robert Bruce, the medieval guerrilla leader who outwitted the English to re-establish an independent Scotland, has been classed a "genius".
Tests carried out by a team of Scottish scientists on a cast of the skull of 'Good King Robert' and th
e application of a formula relating brain size to intelligence have revealed that the 14th-century monarch could have had an IQ of 128.
That puts him just four points below the 132 mark that Mensa says signifies the most intelligent 2% of the population. But the Edinburgh scientists believe Bruce's score is almost certainly an underestimate.
Even at 128 - the average Briton is 100 - the former Scottish ruler would have been capable of leading "a large group with a hierarchical leadership structure". Other military leaders previously estimated to have had high IQs include Oliver Cromwell at 135, George Washington at 140 and Napoleon at 145.
The findings formalise the intellectual status of a Scotsman once derided by his over-confident Plantagenet adversary, Edward II. But that was before his cunning tactics won the 1314 Battle of Bannockburn, securing his reputation among his compatriots for centuries. His philosophical musings about the perseverance of a spider were also, at that stage, unknown.
To the possible relief of Scottish nationalists, the findings also contradict the opinion of Karl Pearson, a Fellow of the Royal Society, who in 1924 pronounced: "To judge him [Bruce] by his skull... the frontal would not popularly indicate great intellectual power."
The scientific team, led by Ian Deary, the professor of differential psychology at Edinburgh University, has published its findings in this month's edition of the American journal Intelligence. The conclusion of their report, entitled "Skull Size and Intelligence and Robert the Bruce's IQ", is that "Robert Bruce's estimated high IQ is congruent with his military, political and other intellectual achievements."
The team base their findings on a recent study of 48 "relatively healthy" and dementia-free elderly Scotsmen, funded by Scotland's Chief Scientist's Office. The 48 volunteers had the space between their ears measured by the University of Edinburgh's Brain Imaging Research Centre to determine the size of the cavity in which the brain is enclosed, which differs between individuals.
They were then subjected to the National Adult Reading Test (NART), which grades individuals' IQs by inviting them to pronounce 50 tricky words.
The tests found a consistent link between brain size and high IQ, and the same process was then applied to Bruce's skull. Two casts have been stored by Edinburgh University's anatomy department since his body was briefly exhumed from Dunfermline Abbey in the early 19th century.
The equation applied to the royal cranium, which measures 198mm long by 154mm wide - a large head even by today's standards - came up with the estimated IQ rating of 128.
Deary said there was only an "approximate" relationship between the circumference of a head and the quality of what it housed but insisted he was "95% confident" that Bruce's IQ fell in the 106 to 130 range, and most probably at the high end.
"Bruce's IQ estimate would put him in the top few percent of the population," he said. "It might even be an underestimate because the NART does not have enough hard questions at the top end."
But how did the Bruce, who died from leprosy in 1329, aged 55, develop such a large head at a time of great deprivation? Deary attributes it to his comfortable home life as the son of nobility as much as genes.
"[Bruce's]... privileged background and lack of privation probably explain in part his having a head size that is large," the report notes.
The results of the cranial postmortem were welcomed by Geoffrey Barrow, emeritus professor of Scottish history at Edinburgh University, biographer of Bruce and one of the study's eight authors.
"This fits in with the man's career," he said.
"Bruce was obviously an excellent person, with great personal courage. He was good at choosing counsellors and, unusually for the time, understood the geography of the west and the Hebrides."
The scientific paper says: "Robert Bruce's defeat of a full English army led by Edward II at Bannockburn showed his outstanding capabilities as a field commander and leader of men. Bruce's command of geography - understanding of directions and distances in Scotland - was altogether remarkable."
It adds that he had a "deep understanding" of the political situation, spoke at least three languages and played a key role in the 1320 Declaration of Arbroath, with its moving appeal to the Pope to recognise Scotland's independence.
"A master of politics moved from a typically dynastic attitude in early life to leadership of the community of the realm. This imaginative leap required intellectual powers of the highest order."
A Mensa spokeswoman said that the results appeared to confirm that Bruce was highly intelligent.
"The average IQ is 100, so clearly he was well above average, as history has borne out," she said. "If he is 128 then he is very close to the top 2%, but in any case it would be very difficult to question Robert Bruce's intelligence."
A 14th-century IQ test
1 If six chroniclers can copy two Bible pages in two minutes, how many chroniclers will it take to copy 18 pages in six minutes?
2 Two pilgrims are on their way to St Andrews. They start at the same point, walk in opposite directions for four miles, turn left and walk another three miles. What is the distance between them?
3 There are 1,200 Scots in the War of Independence. Some have pink and green striped tunics, some are all pink and some are all blue. One third are pure pink. Is it true that 400 Scots are definitely blue?
4 Pope Clement VII and Pope Urban VI are counting their savings. If Clement gives Urban £8 both have the same amount of money. If Urban gives Clement £8, Clement has five times as much as Urban. Who has what?
5 A peasant travels at 9.93mph in order to join the revolt. He returns home, over exactly the same distance, at 3.31mph. What is his average speed over the entire journey, presuming he survives the Black Death?
ANSWERS: 1) 18, 2) 10km, 3) No, the other 800 Scots can be any mix of all blue, pink and green stripes, 4) Urban has £16 and Clement has £32, 5) 4.965mph