GILAN, the westernmost of the three Caspian provinces of Persia, lying between 37° and 38° N. with a breadth varying from 15 to 6o m. Separated on the north from Russia by the little river of Astara, it is bounded on the west by the province of Azerbaijan, on the south by Kazvin and on the east by Ma zandaran. Like all the Caspian provinces of Persia, Gilan consists geographically of two zones; the coastal plain, backed by a well nigh impenetrable jungle; and the forestclad spurs running out northward from the massif of the Elburz range. These zones present an astonishing contrast in climate, landscape and race. Though the Safid Rud (called Kizil Uzun in its upper reaches) is the only river of any volume, the province is abundantly watered by a great number of smaller streams.
The climate of the plains in the neighbourhood of Resht, the capital, is exceedingly damp and relaxing, with a very high rain fall-56 inches having been recorded; yet, over a great part of the area the fall is not sufficiently sure and regular in summer to provide for cultivation without resort to irrigation. The mild and wet winter is broken by the bad-i-germ, or warm wind. The soil is very fertile, consisting mainly of a rich loam lying over sandstone and shingle. The vegetation resembles that of south ern Europe, but owing to the warm humidity which prevails, it is more tropically luxuriant, and in the lower valleys of the Elburz, up to 5,000 ft., there are forest tracts as dense as any Indian jungle.
The prevailing forest trees are box, oak, ash, beech, elm and hornbeam; the first named comes to rare perfection but un fortunately indiscriminate cutting for export has tended to make it scarce. Many kinds of fruit-bearing trees are to be met with but the quality of the fruit they yield is on the whole disappoint ing. Two varieties of wild grape occur but the cultivated vine does not thrive ; the medlar and the fig flourish, as do the wild pomegranate and the water-melon, the latter attaining huge proportions. Oranges and lemons thrive in the gardens, and in the hilly district of Rudbar there is considerable cultivation of olives, but the process of oil extraction in vogue is crude and wasteful. The specialities of Gilan in the direction of fruit are a peculiar variety of pear, in great demand for grafting, and the "Gilan plum" which is well known all over northern Persia.
The fauna is well represented, but tigers, once not uncommon, are now very scarce ; panther, hyaena, jackal, wild boar, are to be found, and two species of deer, the fine Maral stag (Cervus elephus maral) and the Ahu or roedeer (Capreolus pyargus). Among the birds, pheasant, woodcock, duck, teal, geese and various other waterfowl abound.
The fishing industry on the Caspian from this province is very important, but during the World War and onwards the business was practically at a standstill owing to the unaccept able claims advanced by the Soviet Government in regard thereto. Early in 1928, however, the parties came to terms, since when the fisheries have been working satisfactorily.
Of crops, rice, the cultivation of which only became general in comparatively recent years, when it gradually replaced a then moribund silk industry, holds its own as the fundamental produce of Gilan, and about 1911 reached an average yield of 180,000 tons, or five-sixths of the total exported from the country.
Sericulture which was formerly a very important and prac tically the sole industry of Gilan was almost reduced to nothing about 1865 by a mysterious epidemic disease which broke out among silkworms alike in Persia and in France ; but thanks to the researches of the famous bacteriologist, Pasteur, who was deputed by Napoleon III. to study the disease, it was gradually got under control and from 1890 onwards the trade regained some of its former prosperity, so that just before the World War the output of raw silk had risen to 1,200,000 lb., 88% of which was produced in Gilan. Another notable product of the Caspian provinces, though not specially of Gilan, is sugar-cane, for the growth of which the climate seems eminently suited. Tea-planting was introduced into the Lahijan district in 19o1 and production has considerably increased in the last few years, so that Lahijan tea is now procurable in most Persian towns; but more capital is needed to put the industry on a prosperous and progressive footing. The other crop of importance produced in the province is tobacco, to the cultivation of which considerable impetus has been given by the increase in cigarette smoking throughout Persia. Gilan is said to supply the wants of all northern Persia in this direction. Various indications of the ex istence of petroleum have been found in the provinces but no action has yet been taken in the direction of its exploitation.
Estimates of the population of Gilan differ enormously. Lorini, in 1911, put the figure at 340,00o, which was considered high at the time, but a later rough census made for official purposes in 1915, suggested that from 5 to 6 million would be nearer the mark.
The capital of the province, and the most active commercial centre is Resht (q.v.), through which the Tehran-Kazvin-Pahlavi motor road runs, one of the best in the country. The latter place (formerly known as Enzeli) enjoys by far the most lively trade of all the Caspian ports of Persia. The revenue of the province in 1926-27 amounted to nearly 24; million krans.
After remaining long independent, Gilan was conquered by Hulagu Khan, who razed the fortifications of Shamiran to the ground in 1227 and formed it into two small principalities, sep arated by the river Safid Rud and with their capitals at Lahijan and Resht respectively. This remained the position until 1567 when the province was finally incorporated in Persia by the Safavid monarch. It was however occupied by a Russian force in the early part of 1723 and Tahmasp III., the tenth Safavid Shah, being then without a throne, and his country occupied by the Afghans, ceded it, together with Mazandaran and Astarabad, to Peter the Great by treaty. Russian troops remained in occu pation until 1734 when they were obliged to evacuate it.
The derivation of the name Gilan from the modern Persian word gil meaning mud (hence "land of mud") is incorrect. It probably means "land of the Gil," an ancient tribe which classical writers mention as the Gelae.
See H. L. Rabino, Les provinces caspiennes de la Perse. Le Guilan ; J. B. L. Noel, "A reconnaissance in the Caspian provinces of Persia," Geogr. J., 1921, lvii. ; L. S. Fortescue, "The Western Elburz and Persian Azerbaijan," Geogr. J., 1924, lxiii., and "Les provinces caspiennes de la Perse," La Geographie, 1925, xliii.