How to recreate a historic map in R using the sf and ggplot2 packages (CC347)

library(tidyverse)
library(showtext)
library(sf)

font_add("b52", "B52-ULC W00 ULC.ttf")
font_add("vasarely", "vasarely-light.otf")
showtext_auto()
showtext_opts(dpi = 300)


populations <- read_tsv("county_count.tsv") %>%
  mutate(size_category = cut(n,
                             breaks = c(0, 1000, 2500, 5000, 10000,
                                        15000, 20000, 30000, max(n))))

read_sf("GA_AtlasHCB/GA_Historical_Counties/GA_Historical_Counties.shp") %>%
  filter(year(START_DATE) < 1890 & year(END_DATE) > 1890) %>%
  inner_join(., populations, by = c("NAME" = "county")) %>%
  ggplot(aes(fill = size_category)) +
  geom_sf(color = "black", linewidth = 0.1, key_glyph = "point") +
  scale_fill_manual(
    name = NULL,
    breaks = c("(3e+04,3.54e+04]", "(2e+04,3e+04]", "(1.5e+04,2e+04]",
               "(1e+04,1.5e+04]", "(5e+03,1e+04]", "(2.5e+03,5e+03]",
               "(1e+03,2.5e+03]", "(0,1e+03]"),
    values = c("#000000", "#7e6583", "#654321", "#d2b48c", "#dc143c",
               "#ffc0cb", "#ffd700", "#00aa00"),
    labels = c("OVER 30,000 NEGROES", "BETWEEN 20,000 AND 30,000",
               "5,000 TO 20,000", "10,000 TO 15,000", "5,000 TO 10,000",
               " 2,500 TO 5,000", "  1,000 TO 2,500", "     UNDER 1,000"),
    guide = guide_legend(ncol = 2,
                         override.aes = list(shape = 21, size = 6,
                                             stroke = 0.2))
  ) +
  labs(
    title = "NEGRO POPULATION OF GEORGIA BY COUNTIES.",
    subtitle = "1890."
  ) +
  coord_sf(expand = FALSE, clip = "off", xlim = c(-86.4, NA)) +
  theme(
    plot.title.position = "plot",
    plot.title = element_text(family = "b52", hjust = 0.5, size = 12,
                              margin = margin(b = 0, t = 20)),
    plot.subtitle = element_text(family = "b52", hjust = 0.5, size = 8,
                                 margin = margin(b = 80)),
    plot.margin = margin(t = 10, b = 20),
    legend.position = "bottom",
    legend.text = element_text(family = "vasarely", size = 8),
    legend.box.spacing = unit(0, "pt"),
    legend.key.spacing.y = unit(15, "pt"),
    legend.key.spacing.x = unit(10, "pt"),
    axis.ticks = element_blank(),
    axis.text = element_blank(),
    panel.grid = element_blank(),
    panel.background = element_blank()
  )

ggsave("plate_05.png", width = 5, height = 6.21, unit = "in")