Straw hats, while an effective method of shielding one from the sun, sometimes have the reputation within the SCA of being a non-period form of headwear. But, when one looks closely at period illustrations, one can see that straw hats appear in western Europe during the SCA's period, though many are shaped differently than those commonly accessible to SCAdians.

• Illustrations from the Maciejowski Bible, 1250. Farm workers wear flat-crowned straw hats. (Note that the conical hats seen in some illustrations are more related to medieval sumptuary law for Jews.) Many of the men wearing straw hats are wearing a simple linen coif under the straw hat, as seen in this illustration, for example.
  Boaz's wheat is threshed (also here)
  Ruth dines with Boaz
  Boaz's barley
  The Ark comes to Beth-Shemesh
• Kunz von Rosenheim, Manesse Codex (UBH Cod. Pal. germ. 848, fol. 394r), 1300-1330
  A dome-crowned straw hat with a simple hatband (or is that simply the line where the crown meets the brim?) on a woman harvesting wheat.
• A beggar in a straw hat in Meditations on the life of Our Lady (BNF It 115, fol. 8v), ca. 1330-1340
• Detail, Allegory of the Good Government, Effects of Good Government in the Countryside, by Ambrogio Lorenzetti, 1338-40, at the Palazzo Pubblico in Siena
  A flat-topped straw hat is worn by a bearded peasant walking on the road; men working in the fields in the background appear to be wearing round-crown straw hats.
• The Romance of Alexander (Bodl. 264), 1338-1344, fol. 62r
• Tacuinum Sanitatis (BNF Nouvelle acquisition latine 1673), c. 1390-1400: Relatively narrow brim and flat crown on a straw hat worn by a peasant harvesting wheat (fol. 46v)
• Tristan and the shepherds, Tristan de Léonois (BNF Fr. 97, fol. 136v), 1st quarter of the 15th century
• Ruth gleaning, Great Bible (British Library MS Roal 1 E. IX, fol. 62v), c. 1405-1415
• Christine de Pisan presents her book to Louis of Orleans, Collected Works of Christine de Pisan (British Library MS Harley 4431, fol. 95), 1410-1411
• Les tres riches heures du Duc de Berry: June, by the Limbourg brothers, 1412-16
  The two men with scythes at the far right of the image are wearing narrow-brimmed dome-crowned straw hats.
• A shepherd at The Nativity by Friedrich von Villach, c. 1420-1430
• July (fol. 7r), harvesting grain (fol. 7v), and tying a sheaf (fol. 8r), a book of hours (PML M.453) c. 1425-1430
• The Mérode Altarpiece, by the Master of Flémalle, 1427
  A man in the background of the left panel, most easily visible in this detail, piously holds to his chest a flat-topped straw hat (with a bit of an indent in the top of the crown), which has a black hatband. It seems to be of a similar shape to the one worn by Giovanni Arnolfini (see The Arnolfini Wedding below) but of a less extreme height.
• July (fol. 7r) and the Miracle of the Cornfield (fol. 39r), a book of hours (PML M.359), c. 1430-1435
• A man with a hunting horn in the Book of the Hunt (Getty 27), c. 1430-1440
• A close-up shows a texture definitely resembling straw (tinted black), but I am not entirely convinced that this is the only conceivable material that would result in the ridged texture.
• Abegg Triptych by Rogier van der Weyden, 1445
  The donor (far left) has a straw hat of the same sort as Giovanni Arnolfini's.
• Apparition of the Virgin to St. Anthony Abbot and St. George by Pisanello, 1445
• The meadows and the woods (haymaking), Livre des prouffitz champestres et ruraulx (BNF Arsenal 5064, fol. 198v), third quarter of the 15th century
• The Adoration of the Shepherds, by Hugo van der Goes, 1476-79
  This image, the central panel of the Portinari Triptych, features several rustics; as seen in this detail, one of the shepherds holds a round-crowned, narrow-brimmed straw hat to his chest.
• July, a book of hours (PML M.6, fol. 8r), c. 1480
• June, The Hours of Louis XII (Lewis E M 11:20), c. 1490-1510
• June, July, and October in The Grimani Breviary, 1490-1510
  A few styles of straw hats on display. Note that one of the women wears a white (linen?) headdress under her straw hat. The men's hats have a shorter brim, turned up at the sides.
• Nativity by Martin Schongauer
  One of the shepherds clutches a medium-brimmed flat-crowned straw hat.
• July from the Great Book of Hours of Anne of Brittany, c. 1500-1508 (BNF Lat 9474)
  A man's straw hat with narrow brim and flat crown
• A farmer in The Last Judgment at the Kuratiekirche in Kortsch, c. 1500-1525
• Adoration of the Shepherds by Ridolfo Ghirlandaio, 1510 (detail)
• August, The Da Costa Hours (PML M.399, fol. 9v), c. 1515
  A woman wears a straw hat with a narrow brim and a flat-topped crown; a man wears a similar hat with a round crown, but turned up in back; a similar style is seen in the April illustration.
• Scenes from the Story of Joseph by Bacchiacca, c. 1515-1516: The Arrest of his Brethren, The Search for the Cup, The Discovery of the Stolen Cup
• The Holy Family by Joos van Cleve, c. 1515-1520
• Die Augsburger Monatsbilder, Germany, 1520s
  Peasants and farm-workers are seen wearing straw hats in most of the murals, especially in details representing June and July.
• A woman shearing sheep in a book of hours by Jehan de Luc, 1524 (The Hague, MMW, 10 F 33, Fol. 7r)
• Fols. 7r, 8v, and 9r in the Hennessy Book of Hours, c. 1530-1540
• The Miraculous Draught of Fishes by Joachim Beuckelaer, 1563
• Haymaking (details 1 and 2) and The Corn Harvest (details 1 and 2, Pieter Bruegel the Elder, 1565
  The man on the left in the foreground, working with his scythe, wears a dome-crowned, fairly narrow-brimmed straw hat. Two of the women enjoying their afternoon repast also wear straw hats, which are either conical or with a very small crown; it is clear that at least one of the two women wears a simple coif under her straw hat. A larger view of what may be a conical straw hat can be seen in Breugel's The Cripples (1568) where a woman standing behind the main group, wearing a dark-colored overgarment, wears a smaller conical straw hat over a simple coif. The women's hats seem to have a tie which is attached to the inside of the crown, which ties at the back of the head (not under the chin).
• Market Woman with Vegetable Stall, by Pieter Aertsen, 1567
  A flat-topped straw hat, worn over a white kerchief or coif. It seems to be pulled down at the sides, perhaps by a dark-colored ribbon attached to the inside of the straw hat in the middle of the brim. This hat (and attachment) is similar to one worn by a woman on the right-hand side of Aartsen's Market Scene. Three women (perhaps those in the market to sell their wares?) and one man wear straw hats in Aertsen's Market Scene with Christ and the Adulteress (1559); it is not readily apparent that the women are wearing a cap under their straw hats, but they may be wearing a small coif that is covered by the hat, which may explain the white tie under the chin of the women in the foreground (although those ties could be for the straw hat). Related imagery of 16th century Flemish men and women in similar straw hats can be found at Working Womens' Dress in 16th Century Flanders.
• The Farmer, Das Ständebuch, 1568
• Woman selling vegetables by Joachim Beuckelaer
  A man wears a straw hat with a domed crown and a narrow brim.
• A French peasant-woman, Habitus praecipuorum populorum tam virorum quam foeminarum singulari arte depicti, 1577
• Labors of the Months: March, May, June, and October, c. 1580
• The Beaneater, by Annibale Carracci, 1580-90
  The brim on this well-worn straw hat turns up slightly around the edge.
• Peasant woman from the Treviso area and Peasant woman from outskirts of Venice as seen in town on Ascension Day from Vecellio's De gli habiti antichi et moderni di diverse parti del mondo, 1590
• Countryside scene with hunters by Gillis van Coninxloo

Straw hats seem to have become more fashionable -- decorated, reshaped, and in some cases, tinted -- in the early 17th century; examples can be found in Rubens’ Isabella Brant (1609), The Straw Hat (1625), and Helena Fourment; also, Zurbar´n’s depiction of St. Margaret as a shepherdess (c. 1631) and Jacob Jordaens’ portrait of his daughter Elizabeth (1640).